/*

DISKSPD

Copyright(c) Microsoft Corporation
All rights reserved.

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED *AS IS*, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

*/

#pragma once

#include <windows.h>
#include <powersetting.h>
#include <powrprof.h>
#include <VersionHelpers.h>
#include <TraceLoggingProvider.h>
#include <TraceLoggingActivity.h>
#include <evntrace.h>
#include <ctime>
#include <vector>
#include <algorithm>
#include <set>
#include <locale>
#include <codecvt>
#include <Winternl.h>   //ntdll.dll
#include <assert.h>
#include "Histogram.h"
#include "IoBucketizer.h"
#include "ThroughputMeter.h"
#include "Version.h"

using namespace std;

TRACELOGGING_DECLARE_PROVIDER(g_hEtwProvider);

#define DISKSPD_TRACE_INFO      0x00000000
#define DISKSPD_TRACE_RESERVED  0x00000001
#define DISKSPD_TRACE_IO        0x00000100

typedef void (WINAPI *PRINTF)(const char*, va_list);                            //function used for displaying formatted data (printf style)

#define ROUND_DOWN(_x,_alignment)                           \
    ( ((_x)/(_alignment)) * (_alignment) )

#define ROUND_UP(_x,_alignment)                             \
    ROUND_DOWN((_x) + (_alignment) - 1, (_alignment))

#define TB (((UINT64)1)<<40)
#define GB (((UINT64)1)<<30)
#define MB (((UINT64)1)<<20)
#define KB (((UINT64)1)<<10)

#define EXPERIMENT_TPUT_CALC        0x1 // precise ms sleep calculation for low rate throughput control
extern ULONG g_ExperimentFlags;

struct ETWEventCounters
{
    UINT64 ullIORead;                   // Read
    UINT64 ullIOWrite;                  // Write
    UINT64 ullMMTransitionFault;        // Transition fault
    UINT64 ullMMDemandZeroFault;        // Demand Zero fault
    UINT64 ullMMCopyOnWrite;            // Copy on Write
    UINT64 ullMMGuardPageFault;         // Guard Page fault
    UINT64 ullMMHardPageFault;          // Hard page fault
    UINT64 ullNetTcpSend;               // Send
    UINT64 ullNetTcpReceive;            // Receive
    UINT64 ullNetUdpSend;               // Send
    UINT64 ullNetUdpReceive;            // Receive
    UINT64 ullNetConnect;               // Connect
    UINT64 ullNetDisconnect;            // Disconnect
    UINT64 ullNetRetransmit;            // ReTransmit
    UINT64 ullNetAccept;                // Accept
    UINT64 ullNetReconnect;             // ReConnect
    UINT64 ullRegCreate;                // NtCreateKey
    UINT64 ullRegOpen;                  // NtOpenKey
    UINT64 ullRegDelete;                // NtDeleteKey
    UINT64 ullRegQuery;                 // NtQueryKey
    UINT64 ullRegSetValue;              // NtSetValueKey
    UINT64 ullRegDeleteValue;           // NtDeleteValueKey
    UINT64 ullRegQueryValue;            // NtQueryValueKey
    UINT64 ullRegEnumerateKey;          // NtEnumerateKey
    UINT64 ullRegEnumerateValueKey;     // NtEnumerateValueKey
    UINT64 ullRegQueryMultipleValue;    // NtQueryMultipleValueKey
    UINT64 ullRegSetInformation;        // NtSetInformationKey
    UINT64 ullRegFlush;                 // NtFlushKey
    UINT64 ullThreadStart;
    UINT64 ullThreadEnd;
    UINT64 ullProcessStart;
    UINT64 ullProcessEnd;
    UINT64 ullImageLoad;
};

// structure containing informations about ETW session
struct ETWSessionInfo
{
    ULONG ulBufferSize;
    ULONG ulMinimumBuffers;
    ULONG ulMaximumBuffers;
    ULONG ulFreeBuffers;
    ULONG ulBuffersWritten;
    ULONG ulFlushTimer;
    LONG lAgeLimit;
    ULONG ulNumberOfBuffers;
    ULONG ulEventsLost;
    ULONG ulLogBuffersLost;
    ULONG ulRealTimeBuffersLost;
};

// structure containing parameters concerning ETW session provided by user
struct ETWMask
{
    BOOL bProcess;
    BOOL bThread;
    BOOL bImageLoad;
    BOOL bDiskIO;
    BOOL bMemoryPageFaults;
    BOOL bMemoryHardFaults;
    BOOL bNetwork;
    BOOL bRegistry;
    BOOL bUsePagedMemory;
    BOOL bUsePerfTimer;
    BOOL bUseSystemTimer;
    BOOL bUseCyclesCounter;
};

namespace UnitTests
{
    class PerfTimerUnitTests;
    class ProfileUnitTests;
    class TargetUnitTests;
    class IORequestGeneratorUnitTests;
}

class PerfTimer
{
public:

    static UINT64 GetTime();

    static double PerfTimeToMicroseconds(const double);
    static double PerfTimeToMilliseconds(const double);
    static double PerfTimeToSeconds(const double);
    static double PerfTimeToMicroseconds(const UINT64);
    static double PerfTimeToMilliseconds(const UINT64);
    static double PerfTimeToSeconds(const UINT64);

    static UINT64 MicrosecondsToPerfTime(const double);
    static UINT64 MillisecondsToPerfTime(const double);
    static UINT64 SecondsToPerfTime(const double);

private:

    static const UINT64 TIMER_FREQ;
    static UINT64 _GetPerfTimerFreq();

    friend class UnitTests::PerfTimerUnitTests;
};

template <typename T1, typename T2>
class Range
{
public:
    Range(
        T1 Source,
        T1 Span,
        T2 Dest
    ) :
        _src(Source),
        _span(Span),
        _dst(Dest)
    {}

    constexpr bool operator<(const Range<T1, T2>& other) const
    {
        //
        // This is used for comparison of effective distributions during result reporting (dedup).
        //
        // A hole with _span == 0 sorts < range with _span > 0
        // Note that a hole will never match in a find().
        //

        return _src < other._src ||
                (_src == other._src &&
                    (_span < other._span ||
                    (_span == other._span && _dst < other._dst)));
    }

    static Range<T1, T2> const * find(const vector<Range<T1, T2>>& v, T1 c)
    {
        // v must be sorted
        size_t s = 0, mid, e = v.size() - 1;

        while (true)
        {
            mid = s + ((e - s) / 2);
            if (c < v[mid]._src) {
                if (s == mid)
                {
                    return nullptr;
                }
                e = mid - 1;
            }
            else if (c > v[mid]._src + v[mid]._span - 1)
            {
                if (e == mid)
                {
                    return nullptr;
                }
                s = mid + 1;
            }
            else
            {
                return &v[mid];
            }
        }
    }

    T1 _src, _span;
    T2 _dst;
};

typedef Range<UINT32, pair<UINT64, UINT64>> DistributionRange;

enum class DistributionType
{
    None,
    Absolute,
    Percent
};

//
// This code implements Bob Jenkins public domain simple random number generator
// See http://burtleburtle.net/bob/rand/smallprng.html for details
//

class Random
{
public:
    Random(UINT64 ulSeed = 0);

    inline UINT64 Rand64()
    {
        UINT64 e;

        e =           _ulState[0] - _rotl64(_ulState[1], 7);
        _ulState[0] = _ulState[1] ^ _rotl64(_ulState[2], 13);
        _ulState[1] = _ulState[2] + _rotl64(_ulState[3], 37);
        _ulState[2] = _ulState[3] + e;
        _ulState[3] = e + _ulState[0];

        return _ulState[3];
    }

    inline UINT32 Rand32()
    {
        return (UINT32)Rand64();
    }

    void RandBuffer(BYTE *pBuffer, UINT32 ulLength, bool fPseudoRandomOkay);

private:
    UINT64 _ulState[4];
};

struct PercentileDescriptor
{
    double Percentile;
    string Name;
};

class Util
{
public:
    static string DoubleToStringHelper(const double);
    template<typename T> static T QuotientCeiling(T dividend, T divisor)
    {
        return (dividend + divisor - 1) / divisor;
    }

    // True if result is <= ratio.
    // The ratio is on the interval [0, 100]:
    //  0 will never occur (always false)
    //  100 will always occur (always true)

    static bool BooleanRatio(Random *pRand, UINT32 ulRatio)
    {
        return ((pRand->Rand32() % 100 + 1) <= ulRatio);
    }

    //
    // This is close to strtoul[l], returning the next character to parse in the input string.
    // This character can be used for validation (should there be any non-integer remaining),
    // interpreting units that follow the integer (KMGTB), or parsing further (int[<sep><more>])
    // content in the string.
    //
    // Return value indicates whether any integers were parsed to Output. Continue is only modified
    // on success, and will point to the terminator on completion. False is returned on overflow.
    //

    template<typename T>
    static bool ParseUInt(const char* Input, T& Output, const char*& Continue)
    {
        T current = 0, last = 0;
        const char* input = Input;
        bool parsed = false;

        while (*input)
        {
            if (*input < '0' || *input > '9')
            {
                break;
            }

            parsed = true;
            current *= 10;
            current += static_cast<T>(*input) - static_cast<T>('0');

            //
            // Overflow?
            //

            if (current < last)
            {
                parsed = false;
                break;
            }
            last = current;

            input += 1;
        }

        //
        // Return if string was consumed
        //
        //

        if (parsed)
        {
            Continue = input;
            Output = current;
        }

        return parsed;
    }
};

// To keep track of which type of IO was issued
enum class IOOperation
{
    Unknown = 0,
    ReadIO,
    WriteIO
};

class TargetResults
{
public:
    TargetResults() :
        ullFileSize(0),
        ullBytesCount(0),
        ullIOCount(0),
        ullReadBytesCount(0),
        ullReadIOCount(0),
        ullWriteBytesCount(0),
        ullWriteIOCount(0)
    {

    }

    void Add(
        DWORD dwBytesTransferred,
        IOOperation type,
        UINT64 ullIoStartTime,
        UINT64 ullIoEndTime,
        UINT64 ullSpanStartTime,
        bool fMeasureLatency,
        bool fCalculateIopsStdDev
        )
    {
        if (type == IOOperation::ReadIO)
        {
            ullReadBytesCount += dwBytesTransferred;    // update read bytes counter
            ullReadIOCount++;                           // update completed read I/O operations counter
        }
        else
        {
            ullWriteBytesCount += dwBytesTransferred;   // update write bytes counter
            ullWriteIOCount++;                          // update completed write I/O operations counter
        }

        ullBytesCount += dwBytesTransferred;            // update bytes counter
        ullIOCount++;                                   // update completed I/O operations counter

        // end time is 0 if we're not measuring latency
        assert(((fMeasureLatency || fCalculateIopsStdDev) && ullIoEndTime != 0) ||
               (!fMeasureLatency && !fCalculateIopsStdDev));

        if (ullIoEndTime == 0)
        {
            return;
        }

        UINT64 ullDuration = ullIoEndTime - ullIoStartTime;;
        double lfDurationUsec = PerfTimer::PerfTimeToMicroseconds(ullDuration);

        if (fMeasureLatency)
        {
            if (type == IOOperation::ReadIO)
            {
                readLatencyHistogram.Add(static_cast<float>(lfDurationUsec));
            }
            else
            {
                writeLatencyHistogram.Add(static_cast<float>(lfDurationUsec));
            }
        }

        if (fCalculateIopsStdDev)
        {
            UINT64 ullRelativeCompletionTime = ullIoEndTime - ullSpanStartTime;

            if (type == IOOperation::ReadIO)
            {
                readBucketizer.Add(ullRelativeCompletionTime, lfDurationUsec);
            }
            else
            {
                writeBucketizer.Add(ullRelativeCompletionTime, lfDurationUsec);
            }
        }
    }

    string sPath;
    UINT64 ullFileSize;         //size of the file
    UINT64 ullBytesCount;       //number of accessed bytes
    UINT64 ullIOCount;          //number of performed I/O operations
    UINT64 ullReadBytesCount;   //number of bytes read
    UINT64 ullReadIOCount;      //number of performed Read I/O operations
    UINT64 ullWriteBytesCount;  //number of bytes written
    UINT64 ullWriteIOCount;     //number of performed Write I/O operations

    Histogram<float> readLatencyHistogram;
    Histogram<float> writeLatencyHistogram;

    IoBucketizer readBucketizer;
    IoBucketizer writeBucketizer;

    // Effective distribution after applying to target size (if specified/non-empty)
    vector<DistributionRange> vDistributionRange;
};

typedef struct _WAIT_STATS {
    ULONGLONG Wait;
    ULONGLONG ThrottleWait;
    ULONGLONG ThrottleSleep;
    ULONGLONG Lookaside;
    ULONGLONG LookasideCompletion[8]; // 0 == none, 1 == 1, ... 7 = 7+
} WAIT_STATS;

class ThreadResults
{
public:
    ThreadResults()
    {
        WaitStats = { 0 };
    }

    WAIT_STATS WaitStats;
    vector<TargetResults> vTargetResults;
};

class Results
{
public:
    bool fUseETW;
    struct ETWEventCounters EtwEventCounters;
    struct ETWMask EtwMask;
    struct ETWSessionInfo EtwSessionInfo;
    vector<ThreadResults> vThreadResults;
    UINT64 ullTimeCount;
    vector<SYSTEM_PROCESSOR_PERFORMANCE_INFORMATION> vSystemProcessorPerfInfo;
};

typedef void (*CALLBACK_TEST_STARTED)();    //callback function to notify that the measured test is about to start
typedef void (*CALLBACK_TEST_FINISHED)();   //callback function to notify that the measured test has just finished

class ProcessorGroupInformation
{
public:
    WORD _groupNumber;
    BYTE _maximumProcessorCount;
    BYTE _activeProcessorCount;
    KAFFINITY _activeProcessorMask;

    ProcessorGroupInformation() = delete;
    ProcessorGroupInformation(
        WORD Group,
        BYTE MaximumProcessorCount,
        BYTE ActiveProcessorCount,
        KAFFINITY ActiveProcessorMask) :
        _groupNumber(Group),
        _maximumProcessorCount(MaximumProcessorCount),
        _activeProcessorCount(ActiveProcessorCount),
        _activeProcessorMask(ActiveProcessorMask)
    {
    }

    ProcessorGroupInformation(
        WORD Group,
        PROCESSOR_GROUP_INFO& GroupInfo) :
        _groupNumber(Group),
        _maximumProcessorCount(GroupInfo.MaximumProcessorCount),
        _activeProcessorCount(GroupInfo.ActiveProcessorCount),
        _activeProcessorMask(GroupInfo.ActiveProcessorMask)
    {
    }

    // This logic is strictly unaware that sparse processor masks are not possible;
    // address this later, not important. See comments around RelationGroup query.
    bool IsProcessorActive(BYTE Processor) const
    {
        return (IsProcessorValid(Processor) &&
                (((KAFFINITY)1 << Processor) & _activeProcessorMask) != 0);
    }

    bool IsProcessorValid(BYTE Processor) const
    {
        return (Processor < _maximumProcessorCount);
    }
};

class ProcessorNumaInformation
{
public:
    DWORD _ulProcCount;
    DWORD _nodeNumber;
    vector<pair<WORD, KAFFINITY>> _vProcessorMasks;
};

class ProcessorCoreInformation
{
public:
    WORD _groupNumber;
    KAFFINITY _processorMask;
    BYTE _efficiencyClass;
    BYTE _groupCoreNumber;

    ProcessorCoreInformation() = delete;
    ProcessorCoreInformation(
        WORD Group,
        KAFFINITY ProcessorMask,
        BYTE EfficiencyClass) :
        _groupNumber(Group),
        _processorMask(ProcessorMask),
        _efficiencyClass(EfficiencyClass),
        _groupCoreNumber(0)
    {
    }
};

class ProcessorSocketInformation
{
public:
    DWORD _ulProcCount;
    DWORD _ulSocketNumber;
    vector<pair<WORD, KAFFINITY>> _vProcessorMasks;
};

class ProcessorTopology
{
public:
    vector<ProcessorGroupInformation> _vProcessorGroupInformation;
    vector<ProcessorNumaInformation> _vProcessorNumaInformation;
    vector<ProcessorSocketInformation> _vProcessorSocketInformation;
    vector<ProcessorCoreInformation> _vProcessorCoreInformation;

    DWORD _ulProcessorCount;            // total number of (active) processors
    BYTE _ubPerformanceEfficiencyClass; // highest performance class present
    bool _fSMT;                         // any SMT cores present

    ProcessorTopology()
    {
        BOOL fResult;
        PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX pInformation;
        DWORD AllocSize = 1024;
        DWORD ReturnedLength = AllocSize;
        LOGICAL_PROCESSOR_RELATIONSHIP NumaRelation;
        pInformation = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) new char[AllocSize];

        _ulProcessorCount = 0;
        _ubPerformanceEfficiencyClass = 0;
        _fSMT = false;

        ////
        // Group Relations
        ////

        fResult = GetLogicalProcessorInformationEx(RelationGroup, pInformation, &ReturnedLength);
        if (!fResult && GetLastError() == ERROR_INSUFFICIENT_BUFFER)
        {
            delete [] pInformation;
            AllocSize = ReturnedLength;
            pInformation = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) new char[AllocSize];
            fResult = GetLogicalProcessorInformationEx(RelationGroup, pInformation, &ReturnedLength);
        }

        if (fResult)
        {
            // Group information comes back as a single (large) element, not an array.
            assert(ReturnedLength == pInformation->Size);

            //
            // Fill in group topology vector
            //
            // Note: maximum processor count has no utility other than an indication of the
            // bit width of the KAFFINITY mask that might have set values. But:
            //
            //   1) any mask will be a contiguous run of set bits (no sparse holes); there is
            //      no case where a 0 bit will be present to indicate a gap/disabled processor
            //   2) all system APIs (such as the cpu utilization query) are defined over active
            //      processors
            //
            // There are (new?) cases where maximum is represented as > active on large systems,
            // which makes these distinctions critical... active processor count is the only
            // count that matters.
            //
            // For the sake of documentation we do save & report out the masks as reported by the
            // system, but the only ones we look at are limited to cases where we get information
            // in the form of GROUP_AFFINITY, which is just group # and mask (like NUMA and package
            // association).
            //

            for (WORD i = 0; i < pInformation->Group.ActiveGroupCount; i++)
            {
                _vProcessorGroupInformation.emplace_back(
                    i,
                    pInformation->Group.GroupInfo[i]
                    );

                _ulProcessorCount += _vProcessorGroupInformation[i]._activeProcessorCount;
            }
        }

        ////
        // NUMA Relations
        ////

        //
        // Dynamically detect the available NUMA relations. Non-Ex returns exactly one relation and
        // does not define the GroupCount field. Ex scales to return multiple groups for large systems
        // with > 64 per NUMA domain and does populate GroupCount.
        //

        NumaRelation = RelationNumaNodeEx;
        ReturnedLength = AllocSize;
        fResult = GetLogicalProcessorInformationEx(NumaRelation, pInformation, &ReturnedLength);
        if (!fResult && GetLastError() == ERROR_GEN_FAILURE)
        {
            NumaRelation = RelationNumaNode;
            fResult = GetLogicalProcessorInformationEx(NumaRelation, pInformation, &ReturnedLength);
        }
        if (!fResult && GetLastError() == ERROR_INSUFFICIENT_BUFFER)
        {
            delete [] pInformation;
            AllocSize = ReturnedLength;
            pInformation = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) new char[AllocSize];
            fResult = GetLogicalProcessorInformationEx(NumaRelation, pInformation, &ReturnedLength);
        }

        if (fResult)
        {
            PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX cur = pInformation;

            while (ReturnedLength > 0)
            {
                ProcessorNumaInformation node;

                assert(ReturnedLength >= cur->Size);

                if (cur->Size > ReturnedLength)
                {
                    break;
                }

                node._nodeNumber = cur->NumaNode.NodeNumber;
                node._ulProcCount = 0;
                for (WORD i = 0; i < (NumaRelation == RelationNumaNode ? 1 : cur->NumaNode.GroupCount); i++)
                {
                    node._ulProcCount += ProcessorTopology::MaskCount(cur->NumaNode.GroupMasks[i].Mask);
                    node._vProcessorMasks.emplace_back(cur->NumaNode.GroupMasks[i].Group,
                                                       cur->NumaNode.GroupMasks[i].Mask);
                }

                _vProcessorNumaInformation.push_back(node);

                ReturnedLength -= cur->Size;
                cur = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX)((PCHAR)cur + cur->Size);
            }
        }

        ////
        // Socket/Package Relations
        ////

        ReturnedLength = AllocSize;
        fResult = GetLogicalProcessorInformationEx(RelationProcessorPackage, pInformation, &ReturnedLength);
        if (!fResult && GetLastError() == ERROR_INSUFFICIENT_BUFFER)
        {
            delete [] pInformation;
            AllocSize = ReturnedLength;
            pInformation = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) new char[AllocSize];
            fResult = GetLogicalProcessorInformationEx(RelationProcessorPackage, pInformation, &ReturnedLength);
        }

        if (fResult)
        {
            PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX cur = pInformation;

            DWORD socketNumber = 0;
            while (ReturnedLength != 0)
            {
                ProcessorSocketInformation socket;

                assert(ReturnedLength >= cur->Size);

                if (cur->Size > ReturnedLength)
                {
                    break;
                }

                socket._ulProcCount = 0;
                socket._ulSocketNumber = socketNumber;
                for (WORD i = 0; i < cur->Processor.GroupCount; i++)
                {
                    socket._ulProcCount += ProcessorTopology::MaskCount(cur->Processor.GroupMask[i].Mask);
                    socket._vProcessorMasks.emplace_back(cur->Processor.GroupMask[i].Group,
                                                         cur->Processor.GroupMask[i].Mask);
                }

                _vProcessorSocketInformation.push_back(socket);

                ReturnedLength -= cur->Size;
                cur = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX)((PCHAR)cur + cur->Size);
                socketNumber += 1;
            }
        }

        ////
        // Core Relations
        ////

        ReturnedLength = AllocSize;
        fResult = GetLogicalProcessorInformationEx(RelationProcessorCore, pInformation, &ReturnedLength);
        if (!fResult && GetLastError() == ERROR_INSUFFICIENT_BUFFER)
        {
            delete [] pInformation;
            AllocSize = ReturnedLength;
            pInformation = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX) new char[AllocSize];
            fResult = GetLogicalProcessorInformationEx(RelationProcessorCore, pInformation, &ReturnedLength);
        }

        //
        // The EfficiencyClass member was added with Windows 10
        //

        BOOL fEfficiencyClass = false;
        if (IsWindows10OrGreater())
        {
            fEfficiencyClass = true;
        }

        if (fResult)
        {
            PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX cur = pInformation;
            BYTE curEfficiency;

            while (ReturnedLength != 0)
            {
                assert(ReturnedLength >= cur->Size);

                if (cur->Size > ReturnedLength)
                {
                    break;
                }

                //
                // Determine the highest performance core class and presence of SMT as we sweep.
                // Note that SMT is per core and can be asymmetric.
                //

                if (fEfficiencyClass)
                {
                    curEfficiency = cur->Processor.EfficiencyClass;
                    if (_ubPerformanceEfficiencyClass < curEfficiency)
                    {
                        _ubPerformanceEfficiencyClass = curEfficiency;
                    }
                }

                if (cur->Processor.Flags & LTP_PC_SMT)
                {
                    _fSMT = true;
                }

                assert(pInformation->Processor.GroupCount == 1);

                _vProcessorCoreInformation.emplace_back(cur->Processor.GroupMask[0].Group,
                                                        cur->Processor.GroupMask[0].Mask,
                                                        fEfficiencyClass ? cur->Processor.EfficiencyClass : (BYTE)0);

                ReturnedLength -= cur->Size;
                cur = (PSYSTEM_LOGICAL_PROCESSOR_INFORMATION_EX)((PCHAR)cur + cur->Size);
            }

            // Now guarantee ascending order of group number & cpu mask so that group-relative core number can be assigned

            sort(_vProcessorCoreInformation.begin(), _vProcessorCoreInformation.end(),
                [](const ProcessorCoreInformation& a, const ProcessorCoreInformation& b)
                {
                    return a._groupNumber < b._groupNumber ||
                          (a._groupNumber == b._groupNumber && a._processorMask < b._processorMask);
                });

            // Assign group-relative core number

            BYTE coreNumber = 0;
            WORD group = 0;
            for (auto& core : _vProcessorCoreInformation)
            {
                if (core._groupNumber != group)
                {
                    group = core._groupNumber;
                    coreNumber = 0;
                }
                core._groupCoreNumber = coreNumber++;
            }
        }

        // TODO: Get the cache relationships as well???

        delete [] pInformation;
    }

    bool IsGroupValid(WORD Group)
    {
        if (Group < _vProcessorGroupInformation.size())
        {
            return true;
        }
        else
        {
            return false;
        }
    }

    // Return the next active processor in the system, exclusive (Next = true)
    // or inclusive (Next = false) of the input group/processor.
    // Iteration is in order of absolute processor number.
    // This does assume at least one core is active, but that is a given.
    //
    // This logic is strictly unaware that sparse processor masks are not possible;
    // address this later, not important. See comments around RelationGroup query.
    void GetActiveGroupProcessor(WORD& Group, BYTE& Processor, bool Next)
    {
        if (Next)
        {
            Processor++;
        }

        while (!_vProcessorGroupInformation[Group].IsProcessorActive(Processor))
        {
            if (!_vProcessorGroupInformation[Group].IsProcessorValid(Processor))
            {
                Processor = 0;
                if (!IsGroupValid(++Group))
                {
                    Group = 0;
                }
            }
            else
            {
                Processor++;
            }
        }
    }

    //
    // Efficiency of these mappings is not a first order concern. We simply use these to avoid assuming
    // ordering of groups/masks of processors within topology structures. There's strictly no reason,
    // for example, that socket 0 contains the first groups (0, 1, etc.) of processors, at least not
    // documented or guaranteed.
    //

    DWORD GetNumaOfProcessor(WORD Group, BYTE Processor) const
    {
        for (const auto& numa : _vProcessorNumaInformation)
        {
            for (const auto& mask : numa._vProcessorMasks)
            {
                if (mask.first == Group && (mask.second & ((KAFFINITY)1 << Processor)))
                {
                    return numa._nodeNumber;
                }
            }
        }

        assert(false);
        return 0;
    }

    DWORD GetSocketOfProcessor(WORD Group, BYTE Processor) const
    {
        for (const auto& socket : _vProcessorSocketInformation)
        {
            for (const auto& mask : socket._vProcessorMasks)
            {
                if (mask.first == Group && (mask.second & ((KAFFINITY)1 << Processor)))
                {
                    return socket._ulSocketNumber;
                }
            }
        }

        assert(false);
        return 0;
    }

    BYTE GetCoreOfProcessor(WORD Group, BYTE Processor, BYTE& EfficiencyClass) const
    {
        for (const auto& core : _vProcessorCoreInformation)
        {
            if (core._groupNumber == Group && (core._processorMask & ((KAFFINITY)1 << Processor)))
            {
                EfficiencyClass = core._efficiencyClass;
                return core._groupCoreNumber;
            }
        }

        assert(false);
        return 0;
    }

    static unsigned int MaskCount(KAFFINITY Mask)
    {
        //
        // Trivial popcount for affinity mask w/o insn dependency
        //

        unsigned int count = 0;

        while (Mask)
        {
            Mask &= (Mask - 1);
            count++;
        }

        return count;
    }
};

//
// Helper macros for outputting indented XML. They assume a local variable "indent".
// Use the Inc form when outputting the opening tag for a multi-line section: <SomeSection>
// Use Dec for the closing tag: </SomeSection>
//

// start line with indent
#define AddXml(s,str)       { (s).append(indent, ' '); (s) += (str); }
// start new indented section
#define AddXmlInc(s,str)    { (s).append(indent, ' '); indent += 2; (s) += (str); }
// end indented section
#define AddXmlDec(s,str)    { if (indent >= 2) { indent -= 2; }; (s).append(indent, ' '); (s) += (str); }

class SystemInformation
{
private:
    SYSTEMTIME StartTime;

public:
    ProcessorTopology processorTopology;
    string sComputerName;
    string sActivePolicyName;
    string sActivePolicyGuid;

    SystemInformation()
    {
        char buffer[128];
        DWORD cb = _countof(buffer);
        GUID *guid = NULL;
        BOOL fResult;

#pragma prefast(suppress:38020, "Yes, we're aware this is an ANSI API in a UNICODE project")
        fResult = GetComputerNameExA(ComputerNamePhysicalDnsHostname, buffer, &cb);
        if (fResult)
        {
            sComputerName = buffer;
        }

        // capture start time
        GetSystemTime(&StartTime);

        if (PowerGetActiveScheme(NULL, &guid) == ERROR_SUCCESS &&
            PowerReadFriendlyName(NULL, guid, NULL, NULL, NULL, &cb) == ERROR_SUCCESS)
        {
            PUCHAR pwrBuffer;

            if (cb <= _countof(buffer))
            {
                pwrBuffer = (PUCHAR) buffer;
            }
            else
            {
                pwrBuffer = new UCHAR[cb];
            }

            if (PowerReadFriendlyName(NULL, guid, NULL, NULL, pwrBuffer, &cb) == ERROR_SUCCESS)
            {
                // Cast wide string down to basic - all of our current output streams are basic
                wstring wActivePolicyName = (PWCHAR) pwrBuffer;
                std::wstring_convert<std::codecvt_utf8<wchar_t>> cvt;
                sActivePolicyName = cvt.to_bytes(wActivePolicyName);
            }

            if (pwrBuffer != (PVOID) buffer)
            {
                delete pwrBuffer;
            }
        }

        if (sActivePolicyName.empty())
        {
            sActivePolicyName = "<unknown>";
        }

        if (guid)
        {
            sprintf_s(buffer, _countof(buffer),
                "%08lx-%04x-%04x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                guid->Data1, guid->Data2, guid->Data3,
                guid->Data4[0], guid->Data4[1], guid->Data4[2], guid->Data4[3],
                guid->Data4[4], guid->Data4[5], guid->Data4[6], guid->Data4[7]);

            sActivePolicyGuid = buffer;

            LocalFree(guid);
        }
    }

    // for unit test, squelch variable timestamp
    void SystemInformation::ResetTime()
    {
        StartTime = { 0 };
    }

    string SystemInformation::GetText() const
    {
        char szBuffer[128]; // guid (36ch), timestamp and power friendly (up to 64ch)
        int nWritten;
        string sText("System information:\n\n");

        // identify computer which ran the test
        sText += "\tcomputer name: ";
        sText += sComputerName;
        sText += "\n";

        sText += "\tstart time: ";
        if (StartTime.wYear) {

            nWritten = sprintf_s(szBuffer, _countof(szBuffer),
                "%u/%02u/%02u %02u:%02u:%02u UTC",
                StartTime.wYear,
                StartTime.wMonth,
                StartTime.wDay,
                StartTime.wHour,
                StartTime.wMinute,
                StartTime.wSecond);
            assert(nWritten && nWritten < _countof(szBuffer));
            sText += szBuffer;
        }

        sText += "\n\n\tcpu count:\t\t";
        sText += to_string(processorTopology._ulProcessorCount);
        sText += "\n\tcore count:\t\t";
        sText += to_string(processorTopology._vProcessorCoreInformation.size());
        sText += "\n\tgroup count:\t\t";
        sText += to_string(processorTopology._vProcessorGroupInformation.size());
        sText += "\n\tnode count:\t\t";
        sText += to_string(processorTopology._vProcessorNumaInformation.size());
        sText += "\n\tsocket count:\t\t";
        sText += to_string(processorTopology._vProcessorSocketInformation.size());
        sText += "\n\theterogeneous cores:\t";
        sText += processorTopology._ubPerformanceEfficiencyClass ? "y\n" : "n\n";

        sText += "\n\tactive power scheme:\t";
        sText += sActivePolicyName;

        if (!sActivePolicyGuid.empty())
        {
            sText += " (";
            sText += sActivePolicyGuid;
            sText += ")";
        }

        sText += "\n";

        return sText;
    }

    string SystemInformation::GetXml(UINT32 indent) const
    {
        char szBuffer[64]; // enough for 64bit mask (17ch) and timestamp
        int nWritten;
        string sXml;

        AddXmlInc(sXml, "<System>\n");

        // identify computer which ran the test
        AddXml(sXml, "<ComputerName>");
        sXml += sComputerName;
        sXml += "</ComputerName>\n";

        // identify tool version which performed the test
        AddXmlInc(sXml, "<Tool>\n");
        AddXml(sXml,"<Version>" DISKSPD_NUMERIC_VERSION_STRING "</Version>\n");
        AddXml(sXml, "<VersionDate>" DISKSPD_DATE_VERSION_STRING "</VersionDate>\n");
        AddXmlDec(sXml, "</Tool>\n");

        AddXml(sXml, "<RunTime>");
        if (StartTime.wYear) {

            nWritten = sprintf_s(szBuffer, _countof(szBuffer),
                "%u/%02u/%02u %02u:%02u:%02u UTC",
                StartTime.wYear,
                StartTime.wMonth,
                StartTime.wDay,
                StartTime.wHour,
                StartTime.wMinute,
                StartTime.wSecond);
            assert(nWritten && nWritten < _countof(szBuffer));
            sXml += szBuffer;
        }
        sXml += "</RunTime>\n";

        AddXml(sXml, "<PowerScheme Name=\"")
        sXml += sActivePolicyName;
        sXml += "\" Guid=\"";
        sXml += sActivePolicyGuid;
        sXml += "\"/>\n";

        // processor topology
        AddXmlInc(sXml, "<ProcessorTopology Heterogeneous=\"");
        sXml += processorTopology._ubPerformanceEfficiencyClass ? "true\">\n" : "false\">\n";

        for (const auto& g : processorTopology._vProcessorGroupInformation)
        {
            AddXml(sXml, "<Group Group=\"");
            sXml += to_string(g._groupNumber);
            sXml += "\" MaximumProcessors=\"";
            sXml += to_string(g._maximumProcessorCount);
            sXml += "\" ActiveProcessors=\"";
            sXml += to_string(g._activeProcessorCount);
            sXml += "\" ActiveProcessorMask=\"0x";
            nWritten = sprintf_s(szBuffer, _countof(szBuffer), "%Ix", g._activeProcessorMask);
            assert(nWritten && nWritten < _countof(szBuffer));
            sXml += szBuffer;
            sXml += "\"/>\n";

        }
        for (const auto& n : processorTopology._vProcessorNumaInformation)
        {
            AddXmlInc(sXml, "<Node Node=\"");
            sXml += to_string(n._nodeNumber);
            sXml += "\">\n";
            for (const auto& g : n._vProcessorMasks)
            {
                AddXml(sXml, "<Group Group=\"");
                sXml += to_string(g.first);
                sXml += "\" Mask=\"0x";
                nWritten = sprintf_s(szBuffer, _countof(szBuffer), "%Ix", g.second);
                assert(nWritten && nWritten < _countof(szBuffer));
                sXml += szBuffer;
                sXml += "\"/>\n";
            }
            AddXmlDec(sXml, "</Node>\n");
        }
        for (const auto& s : processorTopology._vProcessorSocketInformation)
        {
            AddXmlInc(sXml, "<Socket Socket=\"");
            sXml += to_string(s._ulSocketNumber);
            sXml += "\">\n";
            for (const auto& g : s._vProcessorMasks)
            {
                AddXml(sXml, "<Group Group=\"");
                sXml += to_string(g.first);
                sXml += "\" Mask=\"0x";
                nWritten = sprintf_s(szBuffer, _countof(szBuffer), "%Ix", g.second);
                assert(nWritten && nWritten < _countof(szBuffer));
                sXml += szBuffer;
                sXml += "\"/>\n";
            }
            AddXmlDec(sXml, "</Socket>\n");
        }
        for (const auto& h : processorTopology._vProcessorCoreInformation)
        {
            AddXml(sXml, "<Core Group=\"");
            sXml += to_string(h._groupNumber);
            sXml += "\" Core=\"";
            sXml += to_string(h._groupCoreNumber);
            sXml += "\" Mask=\"0x";
            nWritten = sprintf_s(szBuffer, _countof(szBuffer), "%Ix", h._processorMask);
            assert(nWritten && nWritten < _countof(szBuffer));
            sXml += szBuffer;
            sXml += "\" EfficiencyClass=\"";
            sXml += to_string(h._efficiencyClass);
            sXml += "\"/>\n";
        }

        AddXmlDec(sXml, "</ProcessorTopology>\n");
        AddXmlDec(sXml, "</System>\n");

        return sXml;
    }
};

extern SystemInformation g_SystemInformation;

struct Synchronization
{
    ULONG ulStructSize;     //size of the structure that the caller is aware of (to easier achieve backward compatibility in a future)
    HANDLE hStopEvent;      //an event to be signalled if the scenario is to be stop before time ellapses
    HANDLE hStartEvent;     //an event for signalling start
    CALLBACK_TEST_STARTED pfnCallbackTestStarted;   //a function to be called if the measured test is about to start
    CALLBACK_TEST_FINISHED pfnCallbackTestFinished; //a function to be called as soon as the measrued test finishes
};

#define STRUCT_SYNCHRONIZATION_SUPPORTS(pSynch, Field) ( \
    (NULL != (pSynch)) && \
    ((pSynch)->ulStructSize >= offsetof(struct Synchronization, Field) + sizeof((pSynch)->Field)) \
    )

// caching modes
// cached -> default (-Sb explicitly)
// disableoscache  -> no_intermediate_buffering (-S or -Su)
// disablelocalcache -> cached, but then tear down local rdr cache (-Sr)
enum class TargetCacheMode {
    Undefined = 0,
    Cached,
    DisableOSCache,
    DisableLocalCache
};

// writethrough modes
// off -> default
// on -> (-Sw or implied with -Sh == -Suw/-Swu)
enum class WriteThroughMode {
    Undefined = 0,
    Off,
    On,
};

// memory mapped IO modes
// off -> default
// on -> (-Sm or -Smw)
enum class MemoryMappedIoMode {
    Undefined = 0,
    Off,
    On,
};

// memory mapped IO flush modes
// off / Undefined -> default
// on -> (-Sm or -Smw)
enum class MemoryMappedIoFlushMode {
    Undefined = 0,
    ViewOfFile,
    NonVolatileMemory,
    NonVolatileMemoryNoDrain,
};

enum class IOMode
{
    Unknown,
    Random,
    Sequential,
    Mixed,
    InterlockedSequential,
    ParallelAsync
};

class ThreadTarget
{
public:

    ThreadTarget() :
        _ulThread(0xFFFFFFFF),
        _ulWeight(0)
    {
    }

    void SetThread(UINT32 ulThread) { _ulThread = ulThread; }
    UINT32 GetThread() const { return _ulThread; }

    void SetWeight(UINT32 ulWeight) { _ulWeight = ulWeight; }
    UINT32 GetWeight() const { return _ulWeight; }

    string GetXml(UINT32 indent) const;

private:
    UINT32 _ulThread;
    UINT32 _ulWeight;
};

// Character which leads off a template target definition; e.g. *1, *2
#define TEMPLATE_TARGET_PREFIX ('*')

class Target
{
public:

    Target() :
        _dwBlockSize(64 * 1024),
        _dwRequestCount(2),
        _ullBlockAlignment(0),
        _ulWriteRatio(0),
        _ulRandomRatio(0),
        _ullBaseFileOffset(0),
        _fParallelAsyncIO(false),
        _fInterlockedSequential(false),
        _cacheMode(TargetCacheMode::Cached),
        _writeThroughMode(WriteThroughMode::Off),
        _memoryMappedIoMode(MemoryMappedIoMode::Off),
        _memoryMappedIoNvToken(nullptr),
        _memoryMappedIoFlushMode(MemoryMappedIoFlushMode::Undefined),
        _fZeroWriteBuffers(false),
        _dwThreadsPerFile(1),
        _ullThreadStride(0),
        _fCreateFile(false),
        _fPrecreated(false),
        _ullFileSize(0),
        _ullMaxFileSize(0),
        _fUseBurstSize(false),
        _dwBurstSize(0),
        _dwThinkTime(0),
        _fThinkTime(false),
        _fSequentialScanHint(false),
        _fRandomAccessHint(false),
        _fTemporaryFileHint(false),
        _fUseLargePages(false),
        _mappedViewFileHandle(INVALID_HANDLE_VALUE),
        _mappedView(NULL),
        _ioPriorityHint(IoPriorityHintNormal),
        _ulWeight(1),
        _dwThroughputBytesPerMillisecond(0),
        _dwThroughputIOPS(0),
        _cbRandomDataWriteBuffer(0),
        _sRandomDataWriteBufferSourcePath(),
        _pRandomDataWriteBuffer(nullptr),
        _distributionType(DistributionType::None)
    {
    }

    IOMode GetIOMode() const
    {
        if (GetRandomRatio() == 100)
        {
            return IOMode::Random;
        }
        else if (GetRandomRatio() != 0)
        {
            return IOMode::Mixed;
        }
        else if (GetUseParallelAsyncIO())
        {
            return IOMode::ParallelAsync;
        }
        else if (GetUseInterlockedSequential())
        {
            return IOMode::InterlockedSequential;
        }
        else
        {
            return IOMode::Sequential;
        }
    }

    void SetPath(const string& sPath) { _sPath = sPath; }
    void SetPath(const char *pPath) { _sPath = pPath; }
    const string& GetPath() const { return _sPath; }

    void SetBlockSizeInBytes(DWORD dwBlockSize) { _dwBlockSize = dwBlockSize; }
    DWORD GetBlockSizeInBytes() const { return _dwBlockSize; }

    void SetBlockAlignmentInBytes(UINT64 ullBlockAlignment)
    {
        _ullBlockAlignment = ullBlockAlignment;
    }
    // actual is used in validation to detect unclear/mis-specified intent
    // like -rs<xx> -s
    UINT64 GetBlockAlignmentInBytes(bool actual = false) const
    {
        return _ullBlockAlignment ? _ullBlockAlignment : (actual ? 0 : _dwBlockSize);
    }

    void SetWriteRatio(UINT32 writeRatio) { _ulWriteRatio = writeRatio; }
    UINT32 GetWriteRatio() const { return _ulWriteRatio; }

    void SetRandomRatio(UINT32 randomRatio) { _ulRandomRatio = randomRatio; }
    UINT32 GetRandomRatio() const { return _ulRandomRatio; }

    void SetBaseFileOffsetInBytes(UINT64 ullBaseFileOffset) { _ullBaseFileOffset = ullBaseFileOffset; }
    UINT64 GetBaseFileOffsetInBytes() const { return _ullBaseFileOffset; }
    UINT64 GetThreadBaseRelativeOffsetInBytes(UINT32 ulThreadNo) const { return ulThreadNo * _ullThreadStride; }
    UINT64 GetThreadBaseFileOffsetInBytes(UINT32 ulThreadNo) const { return _ullBaseFileOffset + GetThreadBaseRelativeOffsetInBytes(ulThreadNo); }


    void SetSequentialScanHint(bool fBool) { _fSequentialScanHint = fBool; }
    bool GetSequentialScanHint() const { return _fSequentialScanHint; }

    void SetRandomAccessHint(bool fBool) { _fRandomAccessHint = fBool; }
    bool GetRandomAccessHint() const { return _fRandomAccessHint; }

    void SetTemporaryFileHint(bool fBool) { _fTemporaryFileHint = fBool; }
    bool GetTemporaryFileHint() const { return _fTemporaryFileHint; }

    void SetUseLargePages(bool fBool) { _fUseLargePages = fBool; }
    bool GetUseLargePages() const { return _fUseLargePages; }

    void SetRequestCount(DWORD dwRequestCount) { _dwRequestCount = dwRequestCount; }
    DWORD GetRequestCount() const { return _dwRequestCount; }

    void SetCacheMode(TargetCacheMode cacheMode) { _cacheMode = cacheMode; }
    TargetCacheMode GetCacheMode() const { return _cacheMode;  }

    void SetWriteThroughMode(WriteThroughMode writeThroughMode ) { _writeThroughMode = writeThroughMode; }
    WriteThroughMode GetWriteThroughMode() const { return _writeThroughMode; }

    void SetMemoryMappedIoMode(MemoryMappedIoMode memoryMappedIoMode ) { _memoryMappedIoMode = memoryMappedIoMode; }
    MemoryMappedIoMode GetMemoryMappedIoMode() const { return _memoryMappedIoMode; }

    void SetMemoryMappedIoNvToken(PVOID memoryMappedIoNvToken) { _memoryMappedIoNvToken = memoryMappedIoNvToken; }
    PVOID GetMemoryMappedIoNvToken() const { return _memoryMappedIoNvToken; }

    void SetMemoryMappedIoFlushMode(MemoryMappedIoFlushMode memoryMappedIoFlushMode) { _memoryMappedIoFlushMode = memoryMappedIoFlushMode; }
    MemoryMappedIoFlushMode GetMemoryMappedIoFlushMode() const { return _memoryMappedIoFlushMode; }

    void SetZeroWriteBuffers(bool fBool) { _fZeroWriteBuffers = fBool; }
    bool GetZeroWriteBuffers() const { return _fZeroWriteBuffers; }

    void SetRandomDataWriteBufferSize(UINT64 cbWriteBuffer) { _cbRandomDataWriteBuffer = cbWriteBuffer; }
    UINT64 GetRandomDataWriteBufferSize(void) const { return _cbRandomDataWriteBuffer; }

    void SetRandomDataWriteBufferSourcePath(string sPath) { _sRandomDataWriteBufferSourcePath = sPath; }
    string GetRandomDataWriteBufferSourcePath() const { return _sRandomDataWriteBufferSourcePath; }

    void SetUseBurstSize(bool fBool) { _fUseBurstSize = fBool; }
    bool GetUseBurstSize() const { return _fUseBurstSize; }

    void SetBurstSize(DWORD dwBurstSize) { _dwBurstSize = dwBurstSize; }
    DWORD GetBurstSize() const { return _dwBurstSize; }

    void SetThinkTime(DWORD dwThinkTime) { _dwThinkTime = dwThinkTime; }
    DWORD GetThinkTime() const { return _dwThinkTime; }

    void SetEnableThinkTime(bool fBool)   { _fThinkTime = fBool; }
    bool GetEnableThinkTime() const { return _fThinkTime; }

    void SetThreadsPerFile(DWORD dwThreadsPerFile) { _dwThreadsPerFile = dwThreadsPerFile; }
    DWORD GetThreadsPerFile() const { return _dwThreadsPerFile; }

    void SetCreateFile(bool fBool) { _fCreateFile = fBool; }
    bool GetCreateFile() const { return _fCreateFile; }

    void SetFileSize(UINT64 ullFileSize) { _ullFileSize = ullFileSize; }
    UINT64 GetFileSize() const { return _ullFileSize; } // TODO: InBytes

    void SetMaxFileSize(UINT64 ullMaxFileSize) { _ullMaxFileSize = ullMaxFileSize; }
    UINT64 GetMaxFileSize() const { return _ullMaxFileSize; }

    void SetUseParallelAsyncIO(bool fBool) { _fParallelAsyncIO = fBool; }
    bool GetUseParallelAsyncIO() const { return _fParallelAsyncIO; }

    void SetUseInterlockedSequential(bool fBool) { _fInterlockedSequential = fBool; }
    bool GetUseInterlockedSequential() const { return _fInterlockedSequential; }

    void SetThreadStrideInBytes(UINT64 ullThreadStride) { _ullThreadStride = ullThreadStride; }
    UINT64 GetThreadStrideInBytes() const { return _ullThreadStride; }

    void SetMappedViewFileHandle(HANDLE FileHandle) { _mappedViewFileHandle = FileHandle; }
    HANDLE GetMappedViewFileHandle() const { return _mappedViewFileHandle; }

    void SetMappedView(BYTE *MappedView) { _mappedView = MappedView; }
    BYTE* GetMappedView() const { return _mappedView; }

    void SetIOPriorityHint(PRIORITY_HINT _hint)
    {
        assert(_hint < MaximumIoPriorityHintType);
        _ioPriorityHint = _hint;
    }
    PRIORITY_HINT GetIOPriorityHint() const { return _ioPriorityHint; }

    void SetWeight(UINT32 ulWeight) { _ulWeight = ulWeight; }
    UINT32 GetWeight() const { return _ulWeight; }

    void AddThreadTarget(const ThreadTarget &threadTarget)
    {
        _vThreadTargets.push_back(threadTarget);
    }
    vector<ThreadTarget> GetThreadTargets() const { return _vThreadTargets; }

    void SetPrecreated(bool fBool) { _fPrecreated = fBool; }
    bool GetPrecreated() const { return _fPrecreated; }

    // Convert units to BPMS. Nonzero value of IOPS indicates originally specified units for display/profile.
    void SetThroughputIOPS(DWORD dwIOPS)
    {
        _dwThroughputIOPS = dwIOPS;
        _dwThroughputBytesPerMillisecond = (dwIOPS * _dwBlockSize) / 1000;
    }
    DWORD GetThroughputIOPS() const { return _dwThroughputIOPS; }
    void SetThroughput(DWORD dwThroughputBytesPerMillisecond)
    {
        _dwThroughputIOPS = 0;
        _dwThroughputBytesPerMillisecond = dwThroughputBytesPerMillisecond;
    }
    DWORD GetThroughputInBytesPerMillisecond() const { return _dwThroughputBytesPerMillisecond; }

    string GetXml(UINT32 indent) const;

    bool AllocateAndFillRandomDataWriteBuffer(Random *pRand);
    void FreeRandomDataWriteBuffer();
    BYTE* GetRandomDataWriteBuffer(Random *pRand);

    void SetDistributionRange(const vector<DistributionRange>& v, DistributionType t)
    {
        _vDistributionRange = v; _distributionType = t;

        // Now place final element if IO% is < 100.
        // If this is an absolute specification, it will map to zero length here and
        // conversion will occur at the time of target open to the rest of the target.
        // For the percent specification we place the final element as-if directly stated,
        // consuming the tail length.
        //
        // This done here so that the stated specification is indeed complete, and not left
        // for the effective distribution.
        //
        // TBD this should be moved to a proper Distribution class.

        const DistributionRange& last = *_vDistributionRange.rbegin();

        UINT32 ioCur = last._src + last._span;
        if (ioCur < 100)
        {
            UINT64 targetCur = last._dst.first + last._dst.second;
            if (t == DistributionType::Percent && targetCur < 100)
            {
                // tail is available
                // if tail is not available, this will be caught by validation
                _vDistributionRange.emplace_back(ioCur, 100 - ioCur, make_pair(targetCur, 100 - targetCur));
            }
            else
            {
                _vDistributionRange.emplace_back(ioCur, 100 - ioCur, make_pair(targetCur, 0));
            }
        }
    }
    auto& GetDistributionRange() const { return _vDistributionRange; }
    auto GetDistributionType() const { return _distributionType; }

    DWORD GetCreateFlags(bool fAsync)
    {
        DWORD dwFlags = FILE_ATTRIBUTE_NORMAL;

        if (GetSequentialScanHint())
        {
            dwFlags |= FILE_FLAG_SEQUENTIAL_SCAN;
        }

        if (GetRandomAccessHint())
        {
            dwFlags |= FILE_FLAG_RANDOM_ACCESS;
        }

        if (GetTemporaryFileHint())
        {
            dwFlags |= FILE_ATTRIBUTE_TEMPORARY;
        }

        if (fAsync)
        {
            dwFlags |= FILE_FLAG_OVERLAPPED;
        }

        if (GetCacheMode() == TargetCacheMode::DisableOSCache)
        {
            dwFlags |= FILE_FLAG_NO_BUFFERING;
        }

        if (GetWriteThroughMode( ) == WriteThroughMode::On)
        {
            dwFlags |= FILE_FLAG_WRITE_THROUGH;
        }

        return dwFlags;
    }

private:
    string _sPath;
    DWORD _dwBlockSize;
    DWORD _dwRequestCount;      // TODO: change the name to something more descriptive (OutstandingRequestCount?)

    UINT64 _ullBlockAlignment;
    UINT32 _ulWriteRatio;
    UINT32 _ulRandomRatio;

    UINT64 _ullBaseFileOffset;

    TargetCacheMode _cacheMode;
    WriteThroughMode _writeThroughMode;
    MemoryMappedIoMode _memoryMappedIoMode;
    MemoryMappedIoFlushMode _memoryMappedIoFlushMode;
    PVOID _memoryMappedIoNvToken;
    DWORD _dwThreadsPerFile;
    UINT64 _ullThreadStride;

    UINT64 _ullFileSize;
    UINT64 _ullMaxFileSize;

    DWORD _dwBurstSize;     // number of IOs in a burst
    DWORD _dwThinkTime;     // time to pause before issuing the next burst of IOs

    DWORD _dwThroughputBytesPerMillisecond; // set to 0 to disable throttling
    DWORD _dwThroughputIOPS;                // if IOPS are specified they are converted to BPMS but saved for fidelity to XML/output

    bool _fThinkTime:1;             // variable to decide whether to think between IOs (default is false) (removed by using _dwThinkTime==0?)
    bool _fUseBurstSize:1;          // TODO: "use" or "enable"?; since burst size must be specified with the think time, one variable should be sufficient
    bool _fZeroWriteBuffers:1;
    bool _fCreateFile:1;
    bool _fPrecreated:1;            // used to track which files have been created before the first timespan and which have to be created later
    bool _fParallelAsyncIO:1;
    bool _fInterlockedSequential:1;
    bool _fSequentialScanHint:1;    // open file with the FILE_FLAG_SEQUENTIAL_SCAN hint
    bool _fRandomAccessHint:1;      // open file with the FILE_FLAG_RANDOM_ACCESS hint
    bool _fTemporaryFileHint:1;     // open file with the FILE_ATTRIBUTE_TEMPORARY hint
    bool _fUseLargePages:1;         // Use large pages for IO buffers

    UINT64 _cbRandomDataWriteBuffer;            // if > 0, then the write buffer should be filled with random data
    string _sRandomDataWriteBufferSourcePath;   // file that should be used for filling the write buffer (if the path is not available, use a crypto provider)
    BYTE *_pRandomDataWriteBuffer;              // a buffer used for write data when _cbWriteBuffer > 0; it's shared by all the threads working on this target

    HANDLE _mappedViewFileHandle;
    BYTE *_mappedView;

    PRIORITY_HINT _ioPriorityHint;

    UINT32 _ulWeight;
    vector<ThreadTarget> _vThreadTargets;

    vector<DistributionRange> _vDistributionRange;
    DistributionType _distributionType;

    bool _FillRandomDataWriteBuffer(Random *pRand);

    friend class UnitTests::ProfileUnitTests;
    friend class UnitTests::TargetUnitTests;
};

class AffinityAssignment
{
public:
    WORD wGroup;
    BYTE bProc;

    AffinityAssignment() = delete;
    AffinityAssignment(WORD p_wGroup, BYTE p_bProc) :
        wGroup(p_wGroup),
        bProc(p_bProc)
    {
    }
};

class TimeSpan
{
public:
    TimeSpan() :
        _ulDuration(10),
        _ulWarmUp(5),
        _ulCoolDown(0),
        _ulRandSeed(0),
        _dwThreadCount(0),
        _dwRequestCount(0),
        _fRandomWriteData(false),
        _fDisableAffinity(false),
        _fCompletionRoutines(false),
        _fMeasureLatency(false),
        _fCalculateIopsStdDev(false),
        _ulIoBucketDurationInMilliseconds(1000)
    {
    }

    void ClearAffinityAssignment()
    {
        _vAffinity.clear();
    }
    void AddAffinityAssignment(WORD wGroup, BYTE bProc)
    {
        _vAffinity.emplace_back(wGroup, bProc);
    }
    const auto& GetAffinityAssignments() const { return _vAffinity; }

    void AddTarget(const Target& target)
    {
        _vTargets.push_back(Target(target));
    }

    vector<Target> GetTargets() const { return _vTargets; }

    void SetDuration(UINT32 ulDuration) { _ulDuration = ulDuration; }
    UINT32 GetDuration() const { return _ulDuration; }

    void SetWarmup(UINT32 ulWarmup) { _ulWarmUp = ulWarmup; }
    UINT32 GetWarmup() const { return _ulWarmUp; }

    void SetCooldown(UINT32 ulCooldown) { _ulCoolDown = ulCooldown; }
    UINT32 GetCooldown() const { return _ulCoolDown; }

    void SetRandSeed(UINT32 ulRandSeed) { _ulRandSeed = ulRandSeed; }
    UINT32 GetRandSeed() const { return _ulRandSeed; }

    void SetRandomWriteData(bool fRandomWriteData) { _fRandomWriteData = fRandomWriteData; }
    bool GetRandomWriteData() const { return _fRandomWriteData; }

    void SetThreadCount(DWORD dwThreadCount) { _dwThreadCount = dwThreadCount; }
    DWORD GetThreadCount() const { return _dwThreadCount; }

    void SetRequestCount(DWORD dwRequestCount) { _dwRequestCount = dwRequestCount; }
    DWORD GetRequestCount() const { return _dwRequestCount; }

    void SetDisableAffinity(bool fDisableAffinity) { _fDisableAffinity = fDisableAffinity; }
    bool GetDisableAffinity() const { return _fDisableAffinity; }

    void SetCompletionRoutines(bool fCompletionRoutines) { _fCompletionRoutines = fCompletionRoutines; }
    bool GetCompletionRoutines() const { return _fCompletionRoutines; }

    void SetMeasureLatency(bool fMeasureLatency) { _fMeasureLatency = fMeasureLatency; }
    bool GetMeasureLatency() const { return _fMeasureLatency; }

    void SetCalculateIopsStdDev(bool fCalculateStdDev) { _fCalculateIopsStdDev = fCalculateStdDev; }
    bool GetCalculateIopsStdDev() const { return _fCalculateIopsStdDev; }

    void SetIoBucketDurationInMilliseconds(UINT32 ulIoBucketDurationInMilliseconds) { _ulIoBucketDurationInMilliseconds = ulIoBucketDurationInMilliseconds; }
    UINT32 GetIoBucketDurationInMilliseconds() const { return _ulIoBucketDurationInMilliseconds; }

    string GetXml(UINT32 indent) const;
    void MarkFilesAsPrecreated(const vector<string> vFiles);

private:
    vector<Target> _vTargets;
    UINT32 _ulDuration;
    UINT32 _ulWarmUp;
    UINT32 _ulCoolDown;
    UINT32 _ulRandSeed;
    DWORD _dwThreadCount;
    DWORD _dwRequestCount;
    bool _fRandomWriteData;
    bool _fDisableAffinity;
    vector<AffinityAssignment> _vAffinity;
    bool _fCompletionRoutines;
    bool _fMeasureLatency;
    bool _fCalculateIopsStdDev;
    UINT32 _ulIoBucketDurationInMilliseconds;

    friend class UnitTests::ProfileUnitTests;
};

enum class ResultsFormat
{
    Text,
    Xml
};

enum class PrecreateFiles
{
    None,
    UseMaxSize,
    OnlyFilesWithConstantSizes,
    OnlyFilesWithConstantOrZeroSizes
};

class Profile
{
public:
    Profile() :
        _fProfileOnly(false),
        _fVerbose(false),
        _fVerboseStats(false),
        _dwProgress(0),
        _fEtwEnabled(false),
        _fEtwProcess(false),
        _fEtwThread(false),
        _fEtwImageLoad(false),
        _fEtwDiskIO(false),
        _fEtwMemoryPageFaults(false),
        _fEtwMemoryHardFaults(false),
        _fEtwNetwork(false),
        _fEtwRegistry(false),
        _fEtwUsePagedMemory(false),
        _fEtwUsePerfTimer(false),
        _fEtwUseSystemTimer(false),
        _fEtwUseCyclesCounter(false),
        _resultsFormat(ResultsFormat::Text),
        _precreateFiles(PrecreateFiles::None)
    {
    }

    void ClearTimeSpans()
    {
        _vTimeSpans.clear();
    }

    void AddTimeSpan(const TimeSpan& timeSpan)
    {
        _vTimeSpans.push_back(TimeSpan(timeSpan));
    }

    const vector<TimeSpan>& GetTimeSpans() const { return _vTimeSpans; }

    void SetProfileOnly(bool b) { _fProfileOnly = b; }
    bool GetProfileOnly() const { return _fProfileOnly; }

    void SetVerbose(bool b) { _fVerbose = b; }
    bool GetVerbose() const { return _fVerbose; }

    void SetVerboseStats(bool b) { _fVerboseStats = b; }
    bool GetVerboseStats() const { return _fVerboseStats; }

    void SetProgress(DWORD dwProgress) { _dwProgress = dwProgress; }
    DWORD GetProgress() const { return _dwProgress; }

    void SetCmdLine(string sCmdLine) { _sCmdLine = sCmdLine; }
    string GetCmdLine() const { return _sCmdLine; };

    void SetResultsFormat(ResultsFormat format) { _resultsFormat = format; }
    ResultsFormat GetResultsFormat() const { return _resultsFormat; }

    void SetPrecreateFiles(PrecreateFiles c) { _precreateFiles = c; }
    PrecreateFiles GetPrecreateFiles() const { return _precreateFiles; }

    //ETW
    void SetEtwEnabled(bool b)          { _fEtwEnabled = b; }
    void SetEtwProcess(bool b)          { _fEtwProcess = b; }
    void SetEtwThread(bool b)           { _fEtwThread = b; }
    void SetEtwImageLoad(bool b)        { _fEtwImageLoad = b; }
    void SetEtwDiskIO(bool b)           { _fEtwDiskIO = b; }
    void SetEtwMemoryPageFaults(bool b) { _fEtwMemoryPageFaults = b; }
    void SetEtwMemoryHardFaults(bool b) { _fEtwMemoryHardFaults = b; }
    void SetEtwNetwork(bool b)          { _fEtwNetwork = b; }
    void SetEtwRegistry(bool b)         { _fEtwRegistry = b; }
    void SetEtwUsePagedMemory(bool b)   { _fEtwUsePagedMemory = b; }
    void SetEtwUsePerfTimer(bool b)     { _fEtwUsePerfTimer = b; }
    void SetEtwUseSystemTimer(bool b)   { _fEtwUseSystemTimer = b; }
    void SetEtwUseCyclesCounter(bool b) { _fEtwUseCyclesCounter = b; }

    bool GetEtwEnabled() const          { return _fEtwEnabled; }
    bool GetEtwProcess() const          { return _fEtwProcess; }
    bool GetEtwThread() const           { return _fEtwThread; }
    bool GetEtwImageLoad() const        { return _fEtwImageLoad; }
    bool GetEtwDiskIO() const           { return _fEtwDiskIO; }
    bool GetEtwMemoryPageFaults() const { return _fEtwMemoryPageFaults; }
    bool GetEtwMemoryHardFaults() const { return _fEtwMemoryHardFaults; }
    bool GetEtwNetwork() const          { return _fEtwNetwork; }
    bool GetEtwRegistry() const         { return _fEtwRegistry; }
    bool GetEtwUsePagedMemory() const   { return _fEtwUsePagedMemory; }
    bool GetEtwUsePerfTimer() const     { return _fEtwUsePerfTimer; }
    bool GetEtwUseSystemTimer() const   { return _fEtwUseSystemTimer; }
    bool GetEtwUseCyclesCounter() const { return _fEtwUseCyclesCounter; }

    string GetXml(UINT32 indent) const;
    bool Validate(bool fSingleSpec, SystemInformation *pSystem = nullptr) const;
    void MarkFilesAsPrecreated(const vector<string> vFiles);

private:
    Profile(const Profile& T);

    vector<TimeSpan>_vTimeSpans;
    bool _fVerbose;
    bool _fVerboseStats;
    bool _fProfileOnly;
    DWORD _dwProgress;
    string _sCmdLine;
    ResultsFormat _resultsFormat;
    PrecreateFiles _precreateFiles;

    //ETW
    bool _fEtwEnabled;
    bool _fEtwProcess;
    bool _fEtwThread;
    bool _fEtwImageLoad;
    bool _fEtwDiskIO;
    bool _fEtwMemoryPageFaults;
    bool _fEtwMemoryHardFaults;
    bool _fEtwNetwork;
    bool _fEtwRegistry;
    bool _fEtwUsePagedMemory;
    bool _fEtwUsePerfTimer;
    bool _fEtwUseSystemTimer;
    bool _fEtwUseCyclesCounter;

    friend class UnitTests::ProfileUnitTests;
};

class IORequest
{
public:
    IORequest(Random *pRand) :
        _ioType(IOOperation::ReadIO),
        _pRand(pRand),
        _iCurrentTarget(0),
        _ullStartTime(0),
        _ulRequestIndex(0xFFFFFFFF),
        _ullTotalWeight(0),
        _fEqualWeights(true),
        _ActivityId()
    {
        memset(&_overlapped, 0, sizeof(OVERLAPPED));
    }

    static IORequest *OverlappedToIORequest(OVERLAPPED *pOverlapped)
    {
        return CONTAINING_RECORD(pOverlapped, IORequest, _overlapped);
    }

    OVERLAPPED *GetOverlapped() { return &_overlapped; }

    void AddTarget(Target *pTarget, UINT32 ulWeight)
    {
        _vTargets.push_back(pTarget);
        _vulTargetWeights.push_back(ulWeight);
        _ullTotalWeight += ulWeight;

        if (ulWeight != _vulTargetWeights[0]) {
            _fEqualWeights = false;
        }
    }

    Target *GetCurrentTarget() { return _vTargets[_iCurrentTarget]; }
    size_t GetCurrentTargetIndex() { return _iCurrentTarget; }

    Target *GetNextTarget()
    {
        UINT64 ullWeight;

        if (_vTargets.size() == 1) {
            _iCurrentTarget = 0;
        }
        else if (_fEqualWeights) {
            _iCurrentTarget = _pRand->Rand32() % _vTargets.size();
        }
        else {
            ullWeight = _pRand->Rand64() % _ullTotalWeight;

            for (size_t iTarget = 0; iTarget < _vTargets.size(); iTarget++) {
                if (ullWeight < _vulTargetWeights[iTarget]) {
                    _iCurrentTarget = iTarget;
                    break;
                }

                ullWeight -= _vulTargetWeights[iTarget];
            }
        }

        return GetCurrentTarget();
    }

    void SetIoType(IOOperation ioType) { _ioType = ioType; }
    IOOperation GetIoType() const { return _ioType; }

    void SetStartTime(UINT64 ullStartTime) { _ullStartTime = ullStartTime; }
    UINT64 GetStartTime() const { return _ullStartTime; }

    void SetRequestIndex(UINT32 ulRequestIndex) { _ulRequestIndex = ulRequestIndex; }
    UINT32 GetRequestIndex() const { return _ulRequestIndex; }

    void SetActivityId(GUID ActivityId) { _ActivityId = ActivityId; }
    GUID GetActivityId() const { return _ActivityId; }

private:
    OVERLAPPED _overlapped;
    vector<Target*> _vTargets;
    vector<UINT32> _vulTargetWeights;
    UINT64 _ullTotalWeight;
    bool _fEqualWeights;
    Random *_pRand;
    size_t _iCurrentTarget;
    IOOperation _ioType;
    UINT64 _ullStartTime;
    UINT32 _ulRequestIndex;
    GUID _ActivityId;
};

typedef struct _ACTIVITY_ID {
    UINT32 Thread;
    UINT32 Reserved;
    UINT64 Count;
} ACTIVITY_ID;

C_ASSERT(sizeof(ACTIVITY_ID) == sizeof(GUID));

// Forward declaration
class ThreadTargetState;

class ThreadParameters
{
public:
    ThreadParameters() :
        pProfile(nullptr),
        pTimeSpan(nullptr),
        pullSharedSequentialOffsets(nullptr),
        ulRandSeed(0),
        ulThreadNo(0),
        ulRelativeThreadNo(0)
    {
    }

    const Profile *pProfile;
    const TimeSpan *pTimeSpan;

    vector<Target> vTargets;
    vector<ThreadTargetState> vTargetStates;
    vector<HANDLE> vhTargets;

    vector<size_t> vulReadBufferSize;
    vector<BYTE *> vpDataBuffers;
    vector<IORequest> vIORequest;
    vector<ThroughputMeter> vThroughputMeters;

    // For interlocked sequential access (-si):
    // Pointers to offsets shared between threads, incremented with an interlocked op
    UINT64* pullSharedSequentialOffsets;

    Random *pRand;

    UINT32 ulRandSeed;
    UINT32 ulThreadNo;
    UINT32 ulRelativeThreadNo;

    // accounting
    volatile bool *pfAccountingOn;
    PUINT64 pullStartTime;
    ThreadResults *pResults;

    //progress dots
    DWORD dwIOCnt;

    //group affinity
    WORD wGroupNum;
    DWORD bProcNum;

    HANDLE hStartEvent;

    // TODO: check how it's used
    HANDLE hEndEvent;        //used only in case of completion routines (not for IO Completion Ports)

    bool AllocateAndFillBufferForTarget(const Target& target);
    BYTE* GetReadBuffer(size_t iTarget, size_t iRequest);
    BYTE* GetWriteBuffer(size_t iTarget, size_t iRequest);
    DWORD GetTotalRequestCount() const;
    bool  InitializeMappedViewForTarget(Target& target, DWORD DesiredAccess);

    GUID NextActivityId()
    {
        GUID ActivityId;
        ACTIVITY_ID* ActivityGuid = (ACTIVITY_ID*)&ActivityId;

        ActivityGuid->Thread = ulThreadNo;
        ActivityGuid->Reserved = 0;
        // The count is byte swapped so it's understandable in a trace.
        ActivityGuid->Count = _byteswap_uint64(++_ullActivityCount);

        return ActivityId;
    }

private:
    ThreadParameters(const ThreadParameters& T);
    UINT64 _ullActivityCount;
};

class ThreadTargetState
{
    public:

    ThreadTargetState(
        const ThreadParameters *pTp,
        size_t iTarget,
        UINT64 targetSize
    ) :
        _tp(pTp),
        _target(&_tp->vTargets[iTarget]),
        _targetSize(targetSize),
        _mode(_target->GetIOMode()),

        _nextSeqOffset(0),
        _lastIO(IOOperation::Unknown),
        _sharedSeqOffset(nullptr),
        _ioDistributionSpan(100)
    {
        //
        // Now calculate the maximum base-relative file offset that IO can be issued at.
        //
        // Trim by max file size limit, and reduce by base file offset.
        //

        if (_target->GetMaxFileSize())
        {
            _relTargetSize = _targetSize > _target->GetMaxFileSize() ? _target->GetMaxFileSize() : _targetSize;
        }
        else
        {
            _relTargetSize = _targetSize;
        }

        _relTargetSize -= _target->GetBaseFileOffsetInBytes();

        //
        // Align relative to the maximum offset at which aligned IO could be issued at.
        //

        _relTargetSizeAligned = _relTargetSize - _target->GetBlockSizeInBytes();
        _relTargetSizeAligned -= _relTargetSizeAligned % _target->GetBlockAlignmentInBytes();
        _relTargetSizeAligned += _target->GetBlockAlignmentInBytes();

        // Grab the shared sequential pointer if this is interlocked.

        if (_mode == IOMode::InterlockedSequential)
        {
            assert(_tp->pullSharedSequentialOffsets != nullptr);
            _sharedSeqOffset = &_tp->pullSharedSequentialOffsets[iTarget];
        }

        // Convert and finalize the random distribution stated in the target using final bounds.

        switch (_target->GetDistributionType())
        {
            case DistributionType::Percent:
            {
                UINT32 ioCarry = 0;

                for (auto& r : _target->GetDistributionRange())
                {
                    //
                    // The basic premise is to align the range's bounds to discover whether there are
                    // any aligned offsets within it. To do this we align DOWN. This moves the adjacent
                    // end of this range and base of the next in lockstep.
                    //
                    // There are two basic branches and three subcases in each:
                    //
                    //  * aligned base
                    //  * unaligned base
                    //  * and within each
                    //      * aligned end
                    //      * unaligned end in same alignment unit
                    //      * unaligned end in next/following alignment unit
                    //
                    //  * aligned/aligned will not move b/e, there will be a positive range
                    //  * aligned/unaligned-next will move e in step with the following b
                    //      and there will be a positive range
                    //  * aligned/unaligned-same will result in b=e after aligning; IO at b is
                    //      the only possible IO
                    //
                    // Unaligned base is more interesting due to degenerate spans, spans where the
                    // mimimum %range is smaller than the block alignment. For instance, a 100KiB target
                    // with a 4K alignment has a 1%/1KB minimum and may create these cases.
                    //
                    //  * unaligned/aligned aligns base (down) and there is a positive range
                    //  * unaligned/unaligned-next aligns both down and there is a positive range
                    //  * unaligned/unaligned-same has no aligned offset in the range; we can detect
                    //      this by aligning e first and seeing if it is less than unaligned b. there
                    //      are two subcases:
                    //      * if the prior range is of zero length, we roll this range's IO% onto it -
                    //        this combines two or more adjacent degenerate spans
                    //      * if it was not of zero length, we roll over the IO% to the next/last range
                    //
                    //  Now, in the cases where we have a positive range we may still find our aligned
                    //  base is the same as the prior range - the prior was degenerate and the current
                    //  is not. In this case we need to round our base up so that we do not share a base.
                    //  We may then find that our rounded up base makes us degenerate and ... roll over.
                    //
                    // Note that this is a closed/open interval. The end offset is NOT a member of this
                    // range. Consider an 8KiB file divided 50:50 into two 4KB ranges. The first range is
                    // [0,4KB) and the second is [4KB, 8KB). The IO at offset 4KB belongs to the second
                    // range, not the first.
                    //

                    //
                    // Skip holes. These have the effect of excluding a range of the target by way of
                    // zero IO will be issued to them; the resulting range is still IO 0-100%.
                    //

                    if (!r._span) {
                        continue;
                    }

                    UINT64 b, e;

                    b = ((r._dst.first * _relTargetSizeAligned) / 100);
                    // guarantee end (don't lose it in integer math)
                    if (r._dst.first + r._dst.second == 100)
                    {
                        e = _relTargetSizeAligned;
                    }
                    else
                    {
                        e = b + ((r._dst.second * _relTargetSizeAligned) / 100);
                    }

                    e = ROUND_DOWN(e, _target->GetBlockAlignmentInBytes());

                    // unaligned/unaligned-same
                    // carryover IO% to next/last range
                    if (e < b)
                    {
                        // is the prior range degenerate?
                        // if so, extend its IO%
                        // note that this cannot happen for the first range, so there
                        // will always be a range to look at.
                        if (_vDistributionRange.rbegin()->_dst.first == e)
                        {
                            _vDistributionRange.rbegin()->_span += r._span;
                        }
                        // carry over to next
                        else
                        {
                            ioCarry = r._span;
                        }

                        continue;
                    }

                    b = ROUND_DOWN(b, _target->GetBlockAlignmentInBytes());

                    // Now if b < e (a positive range) we may discover we're adjacent
                    // to a degenerate range. This is the case of re-aligning b up.
                    // Note that the degenerate range logically rounds up - this does
                    // not affect operation, but presents the correct appearance of a
                    // closed/open interval with respect to the subsequent range.
                    // Case: -rdpct10/1:10/1
                    //
                    // It is possible b == e: this is a case where b was already aligned
                    // and we're placing a normal degenerate span. No special handling.

                    if (b < e &&
                        _vDistributionRange.size() &&
                        _vDistributionRange.rbegin()->_dst.first == b)
                    {

                        b += _target->GetBlockAlignmentInBytes();
                        _vDistributionRange.rbegin()->_dst.second += _target->GetBlockAlignmentInBytes();

                        // Now there are two degenerate cases to manage.

                        // if we're dealing with a degenerate at the tail, allow carryover
                        if (b == _relTargetSizeAligned)
                        {
                            ioCarry = r._span;
                            continue;
                        }

                        // otherwise, if the range became degenerate in the up-alignment, it must
                        // combine with the prior degenerate since its logical range is included
                        // with it.
                        if (b == e)
                        {
                            _vDistributionRange.rbegin()->_span += r._span;
                            continue;
                        }

                        // fall through to place re-aligned b/e (non degenerate)
                    }

                    // prefer to roll IO% to the smaller of prior range/this range
                    if (ioCarry &&
                        _vDistributionRange.rbegin()->_span < r._span)
                    {
                        _vDistributionRange.rbegin()->_span += ioCarry;
                        ioCarry = 0;
                    }

                    _vDistributionRange.emplace_back(
                        r._src - ioCarry,
                        r._span + ioCarry,
                        make_pair(b, e - b));

                    ioCarry = 0;
                }

                // Apply trailing carryover to final range, extending it.
                // Guarantee target range extends to aligned size - rollover is always from
                // a degenerate range we could not place directly. We need to gross up the
                // actual tail so that the effective correctly spans the open/closed interval
                // to target size.
                // -rdpct10/96:10/3:80/1 - the last range is degenerate and needs to roll.
                if (ioCarry)
                {
                    DistributionRange& last = *_vDistributionRange.rbegin();

                    last._span += ioCarry;
                    last._dst.second = _relTargetSizeAligned - last._dst.first;
                }
            }
            break;

            case DistributionType::Absolute:
            {
                UINT32 ioUsed = 0;

                for (auto& r : _target->GetDistributionRange())
                {
                    //
                    // The premise for absolute distributions is similar but without the complication of
                    // degenerate ranges. The offsets are provided and we only need to push the last to
                    // the end of the range if it was left open (its length is zero). They do not need to
                    // be aligned, similar to -T thread stride - this is the caller's dilemma. We already
                    // know by validation that IO can be issued in the range since any absolute distribution
                    // with a range < block size would have been rejected.
                    //
                    // If the range was not left open we have two cases:
                    //
                    //  * the end is within the final range
                    //  * the end is past it
                    //
                    // If the end is within the final range that will again be the caller's dilemma, we'll
                    // simply trim the length of that range. If it is past it, we will discard the trailing
                    // ranges and trim the maximum IO% so that they become a proportional specification of the
                    // IO. For instance, if a 10/10/80 winds up with the 80% not addressable in the file, the
                    // maximum IO% trims to 20 and it logically becomes a 50:50 split (10:10).
                    //

                    UINT64 l;

                    //
                    // Skip holes. These have the effect of excluding a range of the target by way of
                    // zero IO will be issued to them; the resulting range is still IO 0-100%.
                    //

                    if (!r._span) {
                        continue;
                    }

                    // beyond end? done, with whatever tail IO% not seen
                    if (r._dst.first >= _relTargetSize)
                    {
                        break;
                    }
                    // open end or spans end? - set to aligned remainder
                    else if (r._dst.second == 0 ||
                             r._dst.first + r._dst.second > _relTargetSize)
                    {
                        // ensure tail can accept IO by blocksize - caller has stated this is aligned by
                        // its specification
                        l = _relTargetSize - r._dst.first;

                        if (l < _target->GetBlockSizeInBytes())
                        {
                            break;
                        }
                    }
                    else
                    {
                        l = r._dst.second;
                    }

                    _vDistributionRange.emplace_back(
                        r._src,
                        r._span,
                        make_pair(r._dst.first, l));

                    ioUsed += r._span;
                }

                // reduce the IO distribution to that specified by the ranges consumed.
                // it is still logically 100%, simply over a range of less than 0-100.
                _ioDistributionSpan = ioUsed;
            }
            break;

            // none
            default:
            break;
        }

        Reset();
    }

    //
    // Reset IO pointer/type state to initial conditions.
    //

    VOID Reset()
    {
        //
        // Now set the (base-relative) initial sequential offset
        //  * sequential: based on thread stride
        //  * mixed: randomized starting position
        //
        // Note this is repeated for ParallelAsync initialization since sequential offset is in the IO request there.
        //

        switch (_mode)
        {
            case IOMode::Sequential:
            _nextSeqOffset = _target->GetThreadBaseRelativeOffsetInBytes(_tp->ulRelativeThreadNo);
            break;

            case IOMode::Mixed:
            _nextSeqOffset = NextRelativeRandomOffset();
            break;

            default:
            break;
        }

        _lastIO = NextIOType(true);
    }

    //
    // Validate whether this thread can start IO given thread stride and file size.
    //

    bool CanStart()
    {
        UINT64 startingFileOffset = _target->GetThreadBaseRelativeOffsetInBytes(_tp->ulRelativeThreadNo);

        if (startingFileOffset + _target->GetBlockSizeInBytes() > _relTargetSize)
        {
            return false;
        }

        return true;
    }

    UINT64 TargetSize()
    {
        return _targetSize;
    }

    VOID InitializeParallelAsyncIORequest(IORequest& ioRequest) const
    {
        ULARGE_INTEGER initialOffset;

        //
        // Bias backwards by one IO so that this functions as the last-IO-issued pointer.
        // It will be incremented to the expected first offset. Note: absolute offset.
        //

        initialOffset.QuadPart = _target->GetThreadBaseFileOffsetInBytes(_tp->ulRelativeThreadNo) - _target->GetBlockAlignmentInBytes();

        ioRequest.GetOverlapped()->Offset = initialOffset.LowPart;
        ioRequest.GetOverlapped()->OffsetHigh = initialOffset.HighPart;
    }

    UINT64 NextRelativeSeqOffset()
    {
        UINT64 nextOffset;

        nextOffset = _nextSeqOffset;

        // Wrap?

        if (nextOffset + _target->GetBlockSizeInBytes() > _relTargetSize) {
            nextOffset = _target->GetThreadBaseRelativeOffsetInBytes(_tp->ulRelativeThreadNo) % _target->GetBlockAlignmentInBytes();
        }

        _nextSeqOffset = nextOffset + _target->GetBlockAlignmentInBytes();

        return nextOffset;
    }

    UINT64 NextRelativeInterlockedSeqOffset()
    {
        UINT64 nextOffset;

        // advance shared and rewind to get offset to use
        nextOffset = InterlockedAdd64((PLONG64) _sharedSeqOffset, _target->GetBlockAlignmentInBytes());
        nextOffset -=  _target->GetBlockAlignmentInBytes();

        nextOffset %= _relTargetSizeAligned;
        return nextOffset;
    }

    UINT64 NextRelativeParaSeqOffset(IORequest& ioRequest)
    {
        ULARGE_INTEGER nextOffset;

        //
        // Note: parallel seq differs from the other sequential cases in that the
        // pointer indicates the prior IO, not the offset to issue the current at.
        // Advance it.
        //

        nextOffset.LowPart = ioRequest.GetOverlapped()->Offset;
        nextOffset.HighPart = ioRequest.GetOverlapped()->OffsetHigh;
        nextOffset.QuadPart -= _target->GetBaseFileOffsetInBytes();     // absolute -> relative
        nextOffset.QuadPart += _target->GetBlockAlignmentInBytes();     // advance past last IO (!)

        // Wrap?

        if (nextOffset.QuadPart + _target->GetBlockSizeInBytes() > _relTargetSize) {
            nextOffset.QuadPart = _target->GetThreadBaseRelativeOffsetInBytes(_tp->ulRelativeThreadNo) % _target->GetBlockAlignmentInBytes();
        }

        return nextOffset.QuadPart;
    }

    UINT64 NextRelativeRandomOffset() const
    {
        UINT64 nextOffset = _tp->pRand->Rand64();
        nextOffset -= nextOffset % _target->GetBlockAlignmentInBytes();

        //
        // With a distribution we choose by bucket. Note the bucket is already aligned.
        //

        if (_vDistributionRange.size())
        {
            auto r = DistributionRange::find(_vDistributionRange, _tp->pRand->Rand64() % _ioDistributionSpan);
            nextOffset %= r->_dst.second;   // trim to range length (already aligned)
            nextOffset += r->_dst.first;    // bump by range base
        }
        // Full width.
        else
        {
            nextOffset %= _relTargetSizeAligned;
        }

        return nextOffset;
    }

    UINT64 NextRelativeMixedOffset(bool& fRandom)
    {
        ULARGE_INTEGER nextOffset;

        fRandom = Util::BooleanRatio(_tp->pRand, _target->GetRandomRatio());

        if (fRandom)
        {
            nextOffset.QuadPart = NextRelativeRandomOffset();
            _nextSeqOffset = nextOffset.QuadPart + _target->GetBlockAlignmentInBytes();
            return nextOffset.QuadPart;
        }

        return NextRelativeSeqOffset();
    }

    IOOperation NextIOType(bool newType)
    {
        IOOperation ioType;

        if (_target->GetWriteRatio() == 0)
        {
           ioType = IOOperation::ReadIO;
        }
        else if (_target->GetWriteRatio() == 100)
        {
            ioType = IOOperation::WriteIO;
        }
        else if (_mode == IOMode::Mixed && !newType)
        {
            // repeat last IO if not needing a new choice (e.g., random)
            ioType = _lastIO;
        }
        else
        {
            ioType = Util::BooleanRatio(_tp->pRand, _target->GetWriteRatio()) ? IOOperation::WriteIO : IOOperation::ReadIO;
            _lastIO = ioType;
        }

        return ioType;
    }

    void NextIORequest(IORequest &ioRequest)
    {
        bool fRandom = false;
        ULARGE_INTEGER nextOffset = { 0 };

        switch (_mode)
        {
            case IOMode::Sequential:
            nextOffset.QuadPart = NextRelativeSeqOffset();
            break;

            case IOMode::InterlockedSequential:
            nextOffset.QuadPart = NextRelativeInterlockedSeqOffset();
            break;

            case IOMode::ParallelAsync:
            nextOffset.QuadPart = NextRelativeParaSeqOffset(ioRequest);
            break;

            case IOMode::Mixed:
            nextOffset.QuadPart = NextRelativeMixedOffset(fRandom);
            break;

            case IOMode::Random:
            nextOffset.QuadPart = NextRelativeRandomOffset();
            fRandom = true;
            break;

            default:
            assert(false);
        }

        //
        //  Convert relative offset to absolute.
        //

        nextOffset.QuadPart += _target->GetBaseFileOffsetInBytes();

        //
        // Move offset into the IO request and decide what IO type will be issued.
        // Mixed which has chosen sequential will repeat last IO type so that seq
        // runs are homogeneous.
        //

        ioRequest.GetOverlapped()->Offset = nextOffset.LowPart;
        ioRequest.GetOverlapped()->OffsetHigh = nextOffset.HighPart;
        ioRequest.SetIoType(NextIOType(fRandom));
    }

    private:

    const ThreadParameters *_tp;
    const Target *_target;
    const UINT64 _targetSize;   // unmodified absolute target size
    const IOMode _mode;         // thread's mode of IO operations to this target (Random, Sequential, etc.)

    //
    // Offsets/sizes are zero-based relative to target base offset, not absolute file offset.
    // Relative size is trimmed with respect to block alignment, if specified.
    //

    UINT64 _relTargetSize;              // relative target size for IO v. base/max
    UINT64 _relTargetSizeAligned;       // relative target size for zero-base aligned IO (applies to: Random, InterlockedSequential)
    UINT64 _nextSeqOffset;              // next IO offset to issue sequential IO at (applies to: Sequential & Mixed)
    volatile UINT64 *_sharedSeqOffset;  // ... for interlocked IO (applies to: InterlockedSequential)
    IOOperation _lastIO;                // last IO type (applies to: Mixed)

public:

    //
    // Random distribution (stated in absolute offsets of target)
    //

    vector<DistributionRange> _vDistributionRange;
    UINT32 _ioDistributionSpan;

    friend class UnitTests::IORequestGeneratorUnitTests;
};

class IResultParser
{
public:
    virtual string ParseResults(const Profile& profile, const SystemInformation& system, vector<Results> vResults) = 0;
    virtual string ParseProfile(const Profile& profile) = 0;
    /// for CrystalDiskMark
    virtual int GetTotalScore() = 0;
    virtual double GetAverageLatency() = 0;
};

class EtwResultParser
{
public:
    static void ParseResults(vector<Results> vResults);

private:
    static void _WriteResults(IOOperation type, const TargetResults& targetResults, size_t uThread);
};