Problem on fma data sync or thread load unbalance

This commit is contained in:
Youmu Liu
2025-09-03 21:29:45 +08:00
parent 125040620b
commit c9442d2b4f
3 changed files with 209 additions and 196 deletions
@@ -41,21 +41,37 @@ using System.Threading;
namespace StgSharp.Mathematics namespace StgSharp.Mathematics
{ {
[StructLayout(LayoutKind.Explicit)] [StructLayout(LayoutKind.Explicit, Size = 32, Pack = 8)]
public unsafe struct MatrixParallelEnumeration
{
[FieldOffset(00)] public MatrixKernel* kernel;
[FieldOffset(08)] public int begin;
[FieldOffset(12)] public int end;
[FieldOffset(16)] public int primCount;
[FieldOffset(20)] public int primStride;
[FieldOffset(24)] public int secCount;
[FieldOffset(28)] public int secStride;
}
[StructLayout(LayoutKind.Explicit, Size = 128, Pack = 8)]
public unsafe struct MatrixParallelTaskPackage public unsafe struct MatrixParallelTaskPackage
{ {
[FieldOffset(0)] public MatrixKernel* left; [FieldOffset(72)] public MatrixKernel* kernel;
[FieldOffset(8)] public MatrixKernel* result; [FieldOffset(0)] public MatrixKernel* Left;
[FieldOffset(16)] public MatrixKernel* right; [FieldOffset(32)] public MatrixKernel* Result;
[FieldOffset(40)] public ScalarDataPacket* scalerPacket; [FieldOffset(64)] public MatrixKernel* Right;
[FieldOffset(24)] public int ComputeMode; [FieldOffset(96)] public ScalarDataPacket* scalerPacket;
[FieldOffset(60)] public int count; [FieldOffset(100)] public int ComputeMode;
[FieldOffset(104)] public int count;
[FieldOffset(108)] public IntPtr executionHandle;
[FieldOffset(48)] public int leftStride; [FieldOffset(0)] public MatrixParallelEnumeration LeftEnum;
[FieldOffset(56)] public int resultStride; [FieldOffset(32)] public MatrixParallelEnumeration ResultEnum;
[FieldOffset(52)] public int rightStride; [FieldOffset(64)] public MatrixParallelEnumeration RightEnum;
[FieldOffset(32)] public IntPtr executionHandle;
} }
@@ -87,43 +103,4 @@ namespace StgSharp.Mathematics
} }
} }
public unsafe class MatrixParallelWrap
{
public Queue<IntPtr>[] cache;
public MatrixParallelWrap(int wrapSize)
{
cache = new Queue<IntPtr>[wrapSize];
for (int i = 0; i < cache.Length; i++) {
cache[i] = new Queue<IntPtr>(8);
}
}
public Span<IntPtr> EnqueuePackage(Span<IntPtr> packageSpan)
{
int idx = 0;
for (; idx < cache.Length; idx++) {
cache[idx].Enqueue(packageSpan[idx]);
}
return packageSpan[idx..];
}
public void EnqueuePackage(MatrixParallelTaskPackage* task)
{
Span<IntPtr> span = stackalloc IntPtr[cache.Length];
MatrixParallelFactory.
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public bool TryGetNextWrapTask(int idInWrap, out IntPtr handle)
{
return cache[idInWrap].TryDequeue(out handle);
}
public record class Handle(int InWrapIndex, MatrixParallelWrap Wrap);
}
} }
@@ -45,24 +45,49 @@ using System.Threading.Tasks;
namespace StgSharp.Mathematics namespace StgSharp.Mathematics
{ {
/*
* Thread wrapping to accelerate matrix operations by dividing threads into groups (wraps).
* For M wraps, each containing an average of N threads, we satisfy the condition M * N = T - 4,
* where T is the total thread count of the CPU. Typically, for modern consumer CPUs, T is around 16.
* For simplicity, let M * N = 16.
*
* The total time complexity for publishing tasks is O(M + N):
* - O(M) accounts for distributing tasks across M wraps.
* - O(N) accounts for threads within each wrap fetching tasks from the wrap queue.
*
* Using the inequality Sqrt(M * N) <= (M + N) / 2 (derived from the arithmetic-geometric mean inequality),
* the optimal configuration occurs when M = N. For M * N = 16, this gives M = N = 4.
*
* To ensure compatibility across a wide range of CPU architectures,
* we allow each wrap to contain either 3 or 4 threads, providing flexibility while maintaining efficiency.
*/
internal static class MatrixParallel internal static class MatrixParallel
{ {
// TODO 解决多线程协调问题,barrier性能不好,MRES时机不好控制,可能可以使用双MRES
private static Thread[] _threads; private static Thread[] _threads;
private static MatrixParallelWrap[] _wraps; private static MatrixParallelWrap[] _wraps;
private static readonly (int a, int b)[] LookupTable = private static readonly (int a, int b)[] LookupTable =
[(1, 1), (0, 2), (3, 0), (2, 1), (1, 2), [(1, 1), (0, 2), (3, 0), (2, 1),
(0, 3), (3, 1), (2, 2), (1, 3), (4, 1), (1, 2), (0, 3), (3, 1), (2, 2), (1, 3),
(3, 2), (2, 3), (1, 4), (0, 5),]; (0, 4), (3, 2), (2, 3), (1, 4), (0, 5),];
private static volatile int RemainThreadCount = 0; private static volatile int RemainThreadCount = 0;
private static readonly ManualResetEventSlim _resetEvent = new(false); private static readonly ManualResetEventSlim _restartEvent = new(false);
private static readonly ManualResetEventSlim _startEvent = new(false);
private static MatrixParallelTaskPackage _totalTask;
private static readonly object _lock = new(); private static readonly object _lock = new();
private static ThreadPriority _AfterWork = ThreadPriority.Lowest; private static ThreadPriority _AfterWork = ThreadPriority.Lowest;
public static ref MatrixParallelTaskPackage TotalTask => ref _totalTask;
public static bool SupportParallel { get; } = Environment.ProcessorCount > 6; public static bool SupportParallel { get; } = Environment.ProcessorCount > 6;
public static bool IsParallelMeaningful { get; } = Environment.ProcessorCount > 6;
internal static MatrixParallelWrap.Handle LeaderHandle { get; private set; }
public static void EndParallel() public static void EndParallel()
{ {
Monitor.Exit(_lock); Monitor.Exit(_lock);
@@ -89,99 +114,19 @@ namespace StgSharp.Mathematics
count = count == 5 ? 4 : count; count = count == 5 ? 4 : count;
int _3wrap = 0, _4wrap = 0; int _3wrap = 0, _4wrap = 0;
_threads = new Thread[count]; _threads = new Thread[count];
if (count < 6) if (count < 6) { } else if (count == 6) { } else { }
{ LeaderHandle = new MatrixParallelWrap.Handle(0, _wraps[0]);
_wraps = new MatrixParallelWrap[1];
_wraps[0] = new MatrixParallelWrap(count);
for (int i = 1; i < count; i++) //first is reverse for leader thread
{
_threads[i] = new Thread(MatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.Highest,
Name = $"StgSharp Matrix Parallel Worker {i}"
};
_threads[i].Start(new MatrixParallelWrap.Handle(i, _wraps[0]));
}
} else if (count == 6)
{
_3wrap = 2;
_threads = new Thread[6];
_wraps = new MatrixParallelWrap[2];
_wraps[0] = new(3);
_wraps[1] = new(3);
for (int i = 1; i < 3; i++) //first is reverse for leader thread
{
_threads[i] = new Thread(MatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.Highest,
Name = $"StgSharp Matrix Parallel Worker {i}"
};
_threads[i].Start(new MatrixParallelWrap.Handle(i, _wraps[0]));
}
for (int i = 3; i < 6; i++)
{
_threads[i] = new Thread(MatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.Highest,
Name = $"StgSharp Matrix Parallel Worker {i}"
};
_threads[i].Start(new MatrixParallelWrap.Handle(i - 3, _wraps[1]));
}
} else
{
(_3wrap, _4wrap) = FastDecompose(count);
_wraps = new MatrixParallelWrap[_3wrap + _4wrap];
int i = 0, wi = 0;
for (; i < 3 * _3wrap; i += 3)
{
MatrixParallelWrap wrap = new(3);
_wraps[wi] = wrap;
wi++;
for (int j = i; j < i + 3; j++)
{
if (j == 0)
{
continue; //first is reverse for leader thread
}
_threads[j] = new Thread(MatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.Highest,
Name = $"StgSharp Matrix Parallel Worker {j}"
};
_threads[j].Start(new MatrixParallelWrap.Handle(j, wrap));
}
}
for (; i < count; i += 4)
{
MatrixParallelWrap wrap = new(4);
_wraps[wi] = wrap;
wi++;
for (int j = i; j < i + 4; j++)
{
_threads[j] = new Thread(MatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.Highest,
Name = $"StgSharp Matrix Parallel Worker {j}"
};
_threads[j].Start(new MatrixParallelWrap.Handle(j, wrap));
}
}
}
} }
public static void LaunchParallel(SleepMode afterWork) public static void LaunchParallel(SleepMode afterWork)
{ {
_resetEvent.Set(); _startEvent.Set();
_restartEvent.Reset();
RemainThreadCount = _threads.Length; RemainThreadCount = _threads.Length;
_AfterWork = (ThreadPriority)afterWork; _AfterWork = (ThreadPriority)afterWork;
_resetEvent.Reset();
} }
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public static void LeadParallel() public static void LeadParallel()
{ {
Monitor.Enter(_lock); Monitor.Enter(_lock);
@@ -189,7 +134,67 @@ namespace StgSharp.Mathematics
public static void PublishTask() { } public static void PublishTask() { }
private static unsafe void MatrixParallelCycle(object obj) public unsafe class MatrixParallelWrap
{
private Queue<IntPtr>[] _cache;
private Thread[] _threads;
private MatrixParallelTaskPackage _wrapTask;
public MatrixParallelWrap(int id, int wrapSize, bool isFirst)
{
ID = id;
_cache = new Queue<IntPtr>[wrapSize];
for (int i = 0; i < _cache.Length; i++) {
_cache[i] = new Queue<IntPtr>(8);
}
_threads = new Thread[wrapSize];
int begin = isFirst ? 0 : 1,end = wrapSize - 1;
for (int i = 0; i < end; i++)
{
_threads[i] = new Thread(CommonMatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.BelowNormal,
Name = $"MPT#{ID}_{i}"
};
_threads[i].Start(new Handle(i, this));
}
_threads[end] = new Thread(SchedulerMatrixParallelCycle)
{
IsBackground = true,
Priority = ThreadPriority.BelowNormal,
Name = $"MPT#{ID}_{end}*"
};
_threads[end].Start(new Handle(end, this));
}
public ref MatrixParallelTaskPackage WrapTask => ref _wrapTask;
public int ID { get; init; }
public Span<IntPtr> EnqueuePackage(Span<IntPtr> packageSpan)
{
int idx = 0;
for (; idx < _cache.Length; idx++) {
_cache[idx].Enqueue(packageSpan[idx]);
}
return packageSpan[idx..];
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
public bool TryGetNextWrapTask(int idInWrap, out IntPtr handle)
{
return _cache[idInWrap].TryDequeue(out handle);
}
public record class Handle(int InWrapIndex, MatrixParallelWrap Wrap);
}
#region ThreadOperation
private static unsafe void CommonMatrixParallelCycle(object obj)
{ {
MatrixParallelWrap.Handle handle = (obj as MatrixParallelWrap.Handle)!; MatrixParallelWrap.Handle handle = (obj as MatrixParallelWrap.Handle)!;
MatrixParallelWrap wrap = handle.Wrap; MatrixParallelWrap wrap = handle.Wrap;
@@ -197,63 +202,88 @@ namespace StgSharp.Mathematics
Thread self = Thread.CurrentThread; Thread self = Thread.CurrentThread;
while (true) while (true)
{ {
while (wrap.TryGetNextWrapTask(inWrapIndex, out IntPtr ptr)) self.Priority = ThreadPriority.Highest;
{ while (wrap.TryGetNextWrapTask(inWrapIndex, out IntPtr ptr)) {
MatrixParallelTaskPackage* p = (MatrixParallelTaskPackage*)ptr; ExecuteTaskPackage((MatrixParallelTaskPackage*)ptr);
MatrixKernel* left = p->left, right = p->left, result = p->result;
int count = p->count;
ScalarDataPacket* scalar = p->scalerPacket;
switch (p->ComputeMode)
{
case 0:
delegate*<MatrixKernel*, MatrixKernel*, void> op_0 = (delegate*<MatrixKernel*, MatrixKernel*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_0(left, result);
left += p->leftStride;
result += p->resultStride;
}
break;
case 1:
delegate*<MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void> op_1 = (delegate*<MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_1(left, result, scalar);
left += p->leftStride;
result += p->resultStride;
}
break;
case 2:
delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, void> op_2 = (delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_2(left, right, result);
right += p->rightStride;
left += p->leftStride;
result += p->resultStride;
}
break;
case 3:
delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void> op_3 = (delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_3(left, right, result, scalar);
right += p->rightStride;
left += p->leftStride;
result += p->resultStride;
}
break;
default:
break;
}
} }
_ = Interlocked.Decrement(ref RemainThreadCount); _ = Interlocked.Decrement(ref RemainThreadCount);
self.Priority = _AfterWork; self.Priority = _AfterWork;
_resetEvent.Wait(); _restartEvent.Wait();
self.Priority = ThreadPriority.Highest;
} }
} }
private static unsafe void ExecuteTaskPackage(MatrixParallelTaskPackage* p)
{
MatrixKernel* left = p->left, right = p->left, result = p->result;
int count = p->count;
ScalarDataPacket* scalar = p->scalerPacket;
switch (p->ComputeMode)
{
case 0:
delegate*<MatrixKernel*, MatrixKernel*, void> op_0 = (delegate*<MatrixKernel*, MatrixKernel*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_0(left, result);
left += p->leftStride;
result += p->resultStride;
}
break;
case 1:
delegate*<MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void> op_1 = (delegate*<MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_1(left, result, scalar);
left += p->leftStride;
result += p->resultStride;
}
break;
case 2:
delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, void> op_2 = (delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_2(left, right, result);
right += p->rightStride;
left += p->leftStride;
result += p->resultStride;
}
break;
case 3:
delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void> op_3 = (delegate*<MatrixKernel*, MatrixKernel*, MatrixKernel*, ScalarDataPacket*, void>)p->executionHandle;
for (int i = 0; i < count; i++)
{
op_3(left, right, result, scalar);
right += p->rightStride;
left += p->leftStride;
result += p->resultStride;
}
break;
default:
break;
}
}
private static unsafe void SchedulerMatrixParallelCycle(object obj)
{
MatrixParallelWrap.Handle handle = (obj as MatrixParallelWrap.Handle)!;
MatrixParallelWrap wrap = handle.Wrap;
int inWrapIndex = handle.InWrapIndex;
Thread self = Thread.CurrentThread;
ref MatrixParallelTaskPackage wt = ref wrap.WrapTask, tt = ref TotalTask;
int l1 = wt
while (true)
{
self.Priority = ThreadPriority.Highest;
while (wrap.TryGetNextWrapTask(inWrapIndex, out IntPtr ptr)) {
ExecuteTaskPackage((MatrixParallelTaskPackage*)ptr);
}
_ = Interlocked.Decrement(ref RemainThreadCount);
self.Priority = _AfterWork;
_restartEvent.Wait();
}
}
#endregion
} }
public enum SleepMode public enum SleepMode
+10 -4
View File
@@ -1,5 +1,6 @@
#include "sn_intrinsic.h" #include "sn_intrinsic.h"
// ans = left * right(T) + ans
INTERNAL void SN_DECL kernel_fma_sse(mat_kernel const *restrict left, INTERNAL void SN_DECL kernel_fma_sse(mat_kernel const *restrict left,
mat_kernel const *restrict right, mat_kernel *restrict ans) mat_kernel const *restrict right, mat_kernel *restrict ans)
{ {
@@ -29,8 +30,13 @@ INTERNAL void SN_DECL kernel_fma_sse(mat_kernel const *restrict left,
_mm_add_ps(ans3, _mm_mul_ps(source3, broadcast)); _mm_add_ps(ans3, _mm_mul_ps(source3, broadcast));
} }
} }
_mm_store_ps(&ans->xmm[0], ans0); source0 = _mm_load_ps(&ans->xmm[0]);
_mm_store_ps(&ans->xmm[1], ans1); source1 = _mm_load_ps(&ans->xmm[1]);
_mm_store_ps(&ans->xmm[2], ans2); source2 = _mm_load_ps(&ans->xmm[2]);
_mm_store_ps(&ans->xmm[3], ans3); source3 = _mm_load_ps(&ans->xmm[3]);
_mm_store_ps(&ans->xmm[0], _mm_add_ps(source0, ans0));
_mm_store_ps(&ans->xmm[1], _mm_add_ps(source1, ans1));
_mm_store_ps(&ans->xmm[2], _mm_add_ps(source2, ans2));
_mm_store_ps(&ans->xmm[3], _mm_add_ps(source3, ans3));
} }