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Marek Lemańczyk committed 2025-09-25 01:07:58 +02:00
1 parent ed8b093472
commit bc4e526946
2 files changed
+643 -639
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PerfectNumbers.Core/Gpu/MersenneNumberDivisorByDivisorGpuTester.cs
+94 -91
View File
@@ -39,17 +39,17 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
private Action<Index1D, ulong, ArrayView<ulong>, ArrayView<byte>> GetCycleKernel(Accelerator accelerator) =>
_cycleKernelCache.GetOrAdd(accelerator, acc => acc.LoadAutoGroupedStreamKernel<Index1D, ulong, ArrayView<ulong>, ArrayView<byte>>(CheckPrimeCycleKernel));
public int GpuBatchSize
{
get => _gpuBatchSize;
set => _gpuBatchSize = Math.Max(1, value);
}
public int GpuBatchSize
{
get => _gpuBatchSize;
set => _gpuBatchSize = Math.Max(1, value);
}
int IMersenneNumberDivisorByDivisorTester.BatchSize
{
get => GpuBatchSize;
set => GpuBatchSize = value;
}
int IMersenneNumberDivisorByDivisorTester.BatchSize
{
get => GpuBatchSize;
set => GpuBatchSize = value;
}
public bool UseDivisorCycles
{
@@ -301,6 +301,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
return Math.Min((1UL << (int)(prime - 1UL)) - 1UL, divisorLimit);
}
// TODO: Since lastProcessed is unused, let's remove it.
private void UpdateStatusUnsafe(ulong lastProcessed, ulong processedCount)
{
if (processedCount == 0UL)
@@ -315,47 +316,46 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
return;
}
// Can we avoid the modulo calculation here? For the higher divisors it may become very expensive. Do we need to calculate the total, too?
ulong total = _lastStatusDivisor + processedCount;
_lastStatusDivisor = total % interval;
// Removed noisy console output; status is tracked internally only.
}
private static void CheckKernel(Index1D index, ulong prime, byte useCycleChecks, ArrayView<MontgomeryDivisorData> divisors, ArrayView<byte> hits)
{
MontgomeryDivisorData divisor = divisors[index];
ulong modulus = divisor.Modulus;
if (modulus <= 1UL || (modulus & 1UL) == 0UL)
{
hits[index] = 0;
return;
}
private static void CheckKernel(Index1D index, ulong prime, byte useCycleChecks, ArrayView<MontgomeryDivisorData> divisors, ArrayView<byte> hits)
{
MontgomeryDivisorData divisor = divisors[index];
ulong modulus = divisor.Modulus;
if (modulus <= 1UL || (modulus & 1UL) == 0UL)
{
hits[index] = 0;
return;
}
ulong exponent = prime;
if (useCycleChecks != 0)
{
ulong cycle = MersenneDivisorCycles.CalculateCycleLengthGpu(modulus);
if (cycle == 0UL)
{
hits[index] = 0;
return;
}
ulong exponent = prime;
if (useCycleChecks != 0)
{
ulong cycle = MersenneDivisorCycles.CalculateCycleLengthGpu(modulus);
if (cycle == 0UL)
{
hits[index] = 0;
return;
}
// TODO: Can we move this back before the GPU call and let CPU handle it? We significantly slowed down after this was moved to GPU.
ulong remainder = prime % cycle;
if (remainder != 0UL)
{
hits[index] = 0;
return;
}
ulong remainder = prime % cycle;
if (remainder != 0UL)
{
hits[index] = 0;
return;
}
exponent = remainder;
}
exponent = remainder;
}
hits[index] = exponent.Pow2MontgomeryMod(divisor) == 1UL ? (byte)1 : (byte)0;
}
hits[index] = exponent.Pow2MontgomeryMod(divisor) == 1UL ? (byte)1 : (byte)0;
}
public sealed class DivisorScanSession : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
{
public sealed class DivisorScanSession : IMersenneNumberDivisorByDivisorTester.IDivisorScanSession
{
private readonly MersenneNumberDivisorByDivisorGpuTester _owner;
private readonly GpuContextPool.GpuContextLease _lease;
private readonly Accelerator _accelerator;
@@ -442,8 +442,8 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
return;
}
ulong cycle = divisorCycle;
bool cycleEnabled = owner._useDivisorCycles && cycle != 0UL;
ulong cycle = divisorCycle;
bool cycleEnabled = owner._useDivisorCycles && cycle != 0UL;
Accelerator accelerator = _accelerator;
Action<Index1D, MontgomeryDivisorData, ArrayView<ulong>, ArrayView<ulong>> kernel = _kernel;
@@ -469,18 +469,19 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
int computeCount = 0;
Span<byte> cycleMaskSpan = default;
if (cycleEnabled)
{
cycleMaskSpan = _cycleMaskHost.AsSpan(0, batchSize);
ArrayView1D<ulong, Stride1D.Dense> primeInputView = _resultsBuffer.View.SubView(0, batchSize);
primeInputView.CopyFromCPU(ref MemoryMarshal.GetReference(primesSlice), batchSize);
ArrayView1D<byte, Stride1D.Dense> cycleMaskView = cycleMaskViewFull.SubView(0, batchSize);
cycleKernel(batchSize, cycle, primeInputView, cycleMaskView);
accelerator.Synchronize();
cycleMaskView.CopyToCPU(ref MemoryMarshal.GetReference(cycleMaskSpan), batchSize);
}
if (cycleEnabled)
{
// TODO: Can we move this back before the GPU call and let CPU handle it? We significantly slowed down after this was moved to GPU.
cycleMaskSpan = _cycleMaskHost.AsSpan(0, batchSize);
ArrayView1D<ulong, Stride1D.Dense> primeInputView = _resultsBuffer.View.SubView(0, batchSize);
primeInputView.CopyFromCPU(ref MemoryMarshal.GetReference(primesSlice), batchSize);
ArrayView1D<byte, Stride1D.Dense> cycleMaskView = cycleMaskViewFull.SubView(0, batchSize);
cycleKernel(batchSize, cycle, primeInputView, cycleMaskView);
accelerator.Synchronize();
cycleMaskView.CopyToCPU(ref MemoryMarshal.GetReference(cycleMaskSpan), batchSize);
}
for (int i = 0; i < batchSize; i++)
for (int i = 0; i < batchSize; i++)
{
if (cycleEnabled && cycleMaskSpan[i] == 0)
{
@@ -488,6 +489,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
continue;
}
// TODO: Avoid one-time use variables like prime here.
ulong prime = primesSlice[i];
primeSpan[computeCount] = prime;
positionSpan[computeCount] = i;
@@ -497,32 +499,32 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
if (computeCount > 0)
{
Span<ulong> exponentSlice = hostSpan[..computeCount];
ulong currentPrime = hasPreviousResidue ? previousPrime : 0UL;
bool hasDeltaSource = hasPreviousResidue;
ulong currentPrime = hasPreviousResidue ? previousPrime : 0UL;
bool hasDeltaSource = hasPreviousResidue;
for (int i = 0; i < computeCount; i++)
{
ulong prime = primeSpan[i];
ulong exponentValue;
if (hasDeltaSource)
{
exponentValue = prime - currentPrime;
}
else
{
exponentValue = prime;
hasDeltaSource = true;
}
for (int i = 0; i < computeCount; i++)
{
ulong prime = primeSpan[i];
ulong exponentValue;
if (hasDeltaSource)
{
exponentValue = prime - currentPrime;
}
else
{
exponentValue = prime;
hasDeltaSource = true;
}
if (cycleEnabled)
{
exponentValue %= cycle;
}
if (cycleEnabled)
{
exponentValue %= cycle;
}
exponentSlice[i] = exponentValue;
exponentSlice[i] = exponentValue;
currentPrime = prime;
}
currentPrime = prime;
}
ArrayView1D<ulong, Stride1D.Dense> exponentView = exponentsView.SubView(0, computeCount);
exponentView.CopyFromCPU(ref MemoryMarshal.GetReference(exponentSlice), computeCount);
@@ -537,6 +539,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
for (int i = 0; i < computeCount; i++)
{
// TODO: Avoid one-time use variables like prime and position here.
int position = positionSpan[i];
ulong stepResidue = exponentSlice[i];
ulong prime = primeSpan[i];
@@ -760,11 +763,11 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
}
}
public DivisorScanSession CreateDivisorSession()
{
lock (_sync)
{
if (!_isConfigured)
public DivisorScanSession CreateDivisorSession()
{
lock (_sync)
{
if (!_isConfigured)
{
throw new InvalidOperationException("ConfigureFromMaxPrime must be called before using the tester.");
}
@@ -773,15 +776,15 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
{
session.Reset();
return session;
}
}
return new DivisorScanSession(this);
}
}
return new DivisorScanSession(this);
}
}
IMersenneNumberDivisorByDivisorTester.IDivisorScanSession IMersenneNumberDivisorByDivisorTester.CreateDivisorSession()
{
return CreateDivisorSession();
}
IMersenneNumberDivisorByDivisorTester.IDivisorScanSession IMersenneNumberDivisorByDivisorTester.CreateDivisorSession()
{
return CreateDivisorSession();
}
}