Heuristic tables split into 2 groups

EvenPerfectBitScanner.Benchmarks/PrimeTesterBenchmarks.cs

@@ -2,6 +2,7 @@ using BenchmarkDotNet.Attributes;
 using BenchmarkDotNet.Jobs;
 using Open.Numeric.Primes;
 using PerfectNumbers.Core;
+using PerfectNumbers.Core.Gpu.Accelerators;
 
 namespace EvenPerfectBitScanner.Benchmarks;
 
@@ -25,6 +26,8 @@ public class PrimeTesterBenchmarks
             return;
         }
 
+		PrimeOrderCalculatorAccelerator.WarmUp();
+		// HeuristicGroupABPrimeTesterAccelerator.WarmUp();
         _ = _heuristicTester.IsPrimeCpu(_candidates[0]);
         _ = _heuristicTester.IsPrimeGpu(_candidates[0]);
         _ = Prime.Numbers.IsPrime(_candidates[0]);
@@ -48,7 +51,7 @@ public class PrimeTesterBenchmarks
         return primeCount;
     }
 
-    // [Benchmark]
+    [Benchmark]
     public int HeuristicGpu()
     {
         HeuristicPrimeTester tester = _heuristicTester;
@@ -66,7 +69,7 @@ public class PrimeTesterBenchmarks
         return primeCount;
     }
 
-    // [Benchmark]
+    [Benchmark]
     public int HeuristicCombinedGpu()
     {
         ulong[] values = _candidates;
@@ -83,7 +86,7 @@ public class PrimeTesterBenchmarks
         return primeCount;
     }
 
-    // [Benchmark]
+    [Benchmark]
     public int HeuristicCombinedCpu()
     {
         ulong[] values = _candidates;

EvenPerfectBitScanner/Program.cs

@@ -628,7 +628,7 @@ internal static class Program
 		{
 			if (!(_runPrimesOnCpu
 					? PrimeTester.IsPrime(p)
-					: PrimeTester.IsPrimeGpu(p)))
+					: HeuristicCombinedPrimeTester.IsPrimeGpu(p)))
 			{
 				_lastCompositeP = true;
 				return false;

PerfectNumbers.Core.Tests/MersenneNumberDivisorByDivisorTesterTests.cs

@@ -83,7 +83,7 @@ public class MersenneNumberDivisorByDivisorTesterTests
                 throw new NotSupportedException();
             }
 
-            public void Dispose()
+            public void Return()
             {
             }
         }

PerfectNumbers.Core.Tests/MersenneNumberDivisorCpuTesterTests.cs

@@ -47,7 +47,7 @@ public class MersenneNumberDivisorCpuTesterTests
                 }
                 finally
                 {
-                        session.Dispose();
+                        session.Return();
                 }
         }
 
@@ -72,7 +72,7 @@ public class MersenneNumberDivisorCpuTesterTests
                 }
                 finally
                 {
-                        session.Dispose();
+                        session.Return();
                 }
         }
 
@@ -97,7 +97,7 @@ public class MersenneNumberDivisorCpuTesterTests
                 }
                 finally
                 {
-                        session.Dispose();
+                        session.Return();
                 }
         }
 }

PerfectNumbers.Core.Tests/MersenneNumberDivisorGpuTesterTests.cs

@@ -161,7 +161,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 
@@ -189,7 +189,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 
@@ -217,7 +217,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 
@@ -246,7 +246,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 
@@ -275,7 +275,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 
@@ -344,7 +344,7 @@ public class MersenneNumberDivisorGpuTesterTests
         }
         finally
         {
-            session.Dispose();
+            session.Return();
         }
     }
 }

PerfectNumbers.Core/Cpu/MersenneCpuDivisorScanSession.cs

@@ -62,7 +62,7 @@ internal sealed class MersenneCpuDivisorScanSession : IMersenneNumberDivisorByDi
         }
     }
 
-    public void Dispose()
+    public void Return()
     {
         ThreadStaticPools.ReturnMersenneCpuDivisorSession(this);
     }

PerfectNumbers.Core/Cpu/MersenneNumberDivisorByDivisorCpuTester.cs

@@ -2,6 +2,7 @@ using System.Collections.Generic;
 using System.Runtime.CompilerServices;
 using PerfectNumbers.Core;
 using PerfectNumbers.Core.Gpu;
+using PerfectNumbers.Core.Gpu.Accelerators;
 
 namespace PerfectNumbers.Core.Cpu;
 
@@ -131,7 +132,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 
 		// Intentionally recomputes factorizations without a per-thread cache.
 		// The previous factor cache recorded virtually no hits and only slowed down the scan.
-        DivisorCycleCache cycleCache = DivisorCycleCache.Shared;
+		_ = DivisorCycleCache.Shared;
 
 		ulong stepHigh = step.High;
 		ulong stepLow = step.Low;
@@ -201,6 +202,8 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 		remainder7 = (byte)((((divisorHigh % 7UL) * 2UL) + (divisorLow % 7UL)) % 7UL);
 		remainder11 = (byte)((((divisorHigh % 11UL) * 5UL) + (divisorLow % 11UL)) % 11UL);
 
+		var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
+
 		while (divisor.CompareTo(limit) <= 0)
 		{
 			bool passesSmallModuli = remainder3 != 0 && remainder7 != 0 && remainder11 != 0;
@@ -217,6 +220,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 				// else
 				{
 					if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
+							gpu,
 							candidate,
 							prime,
 							divisorData,
@@ -241,6 +245,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 					// A cycle equal to the tested exponent (which is prime in this path) guarantees that the candidate divides
 					// the corresponding Mersenne number because the order of 2 modulo the divisor is exactly p.
 					processedAll = true;
+					HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 					return true;
 				}
 
@@ -257,6 +262,8 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 			remainder7 = AddMod7(remainder7, step7);
 			remainder11 = AddMod11(remainder11, step11);
 		}
+
+		HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 		processedAll = true;
 		return false;
 	}
@@ -282,6 +289,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 		processedAll = false;
 
 		bool canAdvance = step <= limit;
+		var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
 		if (!canAdvance)
 		{
 			if (divisor <= limit)
@@ -291,6 +299,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 					MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
 					ulong divisorCycle;
 					if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
+							gpu,
 							divisor,
 							prime,
 							divisorData,
@@ -310,6 +319,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 					if (divisorCycle == prime)
 					{
 						processedAll = true;
+						HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 						return true;
 					}
 
@@ -340,6 +350,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 				MontgomeryDivisorData divisorData = MontgomeryDivisorData.FromModulus(divisor);
 				ulong divisorCycle;
 				if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
+						gpu,
 						divisor,
 						prime,
 						divisorData,
@@ -359,6 +370,7 @@ public sealed class MersenneNumberDivisorByDivisorCpuTester : IMersenneNumberDiv
 				if (divisorCycle == prime)
 				{
 					processedAll = true;
+					HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 					return true;
 				}
 

PerfectNumbers.Core/Gpu/Accelerators/AcceleratorExtensions.cs

@@ -0,0 +1,34 @@
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu.Accelerators;
+
+public static class AcceleratorExtensions
+{
+	public static MemoryBuffer1D<ulong, Stride1D.Dense> CopySpanToDevice(this Accelerator accelerator, AcceleratorStream stream, in ulong[] span)
+	{
+		MemoryBuffer1D<ulong, Stride1D.Dense>? buffer;
+		buffer = accelerator.Allocate1D(stream, span);
+
+		return buffer;
+	}
+
+	public static MemoryBuffer1D<ulong, Stride1D.Dense> CopyUintSpanToDevice(this Accelerator accelerator, AcceleratorStream stream, ReadOnlySpan<uint> span)
+	{
+		MemoryBuffer1D<ulong, Stride1D.Dense>? buffer;
+		buffer = accelerator.Allocate1D<ulong>(span.Length);
+
+		if (!span.IsEmpty)
+		{
+			var converted = new ulong[span.Length];
+			for (int i = 0; i < span.Length; i++)
+			{
+				converted[i] = span[i];
+			}
+
+			buffer.View.CopyFromCPU(stream, converted);
+		}
+
+		return buffer;
+	}
+}

PerfectNumbers.Core/Gpu/Accelerators/HeuristicCombinedPrimeTesterAccelerator.cs

@@ -0,0 +1,147 @@
+using System.Runtime.CompilerServices;
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu.Accelerators;
+
+public sealed class HeuristicCombinedPrimeTesterAccelerator
+{
+	#region Pool
+
+	[ThreadStatic]
+	private static Queue<HeuristicCombinedPrimeTesterAccelerator>? Pool;
+
+	public static void WarmUp(int acceleratorIndex, AcceleratorStream stream)
+	{
+		Console.WriteLine($"Preparing heuristic accelerator {acceleratorIndex}...");
+		HeuristicGpuCombinedTables.WarmUp(acceleratorIndex, stream);
+		// _ = GpuKernelPool.GetOrAddKernels(accelerator, stream, KernelType.None);
+		// KernelContainer kernels = GpuKernelPool.GetOrAddKernels(accelerator, stream);
+		// GpuStaticTableInitializer.EnsureStaticTables(accelerator, kernels, stream);
+		Console.WriteLine($"Heuristic accelerator {acceleratorIndex} is ready");
+	}
+
+	public static HeuristicCombinedPrimeTesterAccelerator Rent(int minBufferCapacity = 1)
+	{
+		var pool = Pool ??= new();
+		if (!pool.TryDequeue(out var lease))
+		{
+			lease = new HeuristicCombinedPrimeTesterAccelerator(minBufferCapacity);
+		}
+		else
+		{
+			lease.EnsureCapacity(minBufferCapacity);
+		}
+
+		return lease;
+	}
+
+	public static void Return(HeuristicCombinedPrimeTesterAccelerator lease)
+	{
+		var pool = Pool ??= new();
+		pool.Enqueue(lease);
+	}
+
+	public static void DisposeAll()
+	{
+		if (Pool != null)
+		{
+			while (Pool.TryDequeue(out var lease))
+			{
+				lease.DisposeResources();
+			}
+		}
+	}
+
+	public static void Clear()
+	{
+		if (Pool != null)
+		{
+			var retained = new List<HeuristicCombinedPrimeTesterAccelerator>();
+			while (Pool.TryDequeue(out var lease))
+			{
+				lease.DisposeResources();
+			}
+		}
+	}
+
+	#endregion
+
+	public readonly HeuristicGpuCombinedDivisorTables DivisorTables;
+	internal readonly Context Context;
+	public readonly Accelerator Accelerator;
+	public readonly Kernel HeuristicCombinedTrialDivisionKernel;
+
+	public MemoryBuffer1D<ulong, Stride1D.Dense>? Input = null;
+	public MemoryBuffer1D<byte, Stride1D.Dense>? Output = null;
+	public MemoryBuffer1D<int, Stride1D.Dense>? HeuristicFlag = null!;
+	public int BufferCapacity;
+
+	private HeuristicGpuCombinedTables _sharedTables;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding1 => _sharedTables.HeuristicCombinedDivisorsEnding1;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding1 => _sharedTables.HeuristicCombinedDivisorSquaresEnding1;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding3 => _sharedTables.HeuristicCombinedDivisorsEnding3;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding3 => _sharedTables.HeuristicCombinedDivisorSquaresEnding3;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding7 => _sharedTables.HeuristicCombinedDivisorsEnding7;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding7 => _sharedTables.HeuristicCombinedDivisorSquaresEnding7;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding9 => _sharedTables.HeuristicCombinedDivisorsEnding9;
+	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding9 => _sharedTables.HeuristicCombinedDivisorSquaresEnding9;
+
+	private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
+	internal readonly int AcceleratorIndex;
+
+	public HeuristicCombinedPrimeTesterAccelerator(int minBufferCapacity)
+	{
+		var acceleratorIndex = AcceleratorPool.Shared.Rent();
+		AcceleratorIndex = acceleratorIndex;
+		Accelerator accelerator = _accelerators[acceleratorIndex];
+		Context = accelerator.Context;
+
+		Accelerator = accelerator;
+		EnsureCapacity(minBufferCapacity);
+
+		HeuristicCombinedTrialDivisionKernel = KernelUtil.GetKernel(accelerator.LoadAutoGroupedStreamKernel<Index1D, byte, ArrayView<int>, ulong, ulong, HeuristicGpuCombinedDivisorTables>(PrimeTesterKernels.HeuristicTrialCombinedDivisionKernel));
+
+		AcceleratorStream stream = AcceleratorStreamPool.Rent(acceleratorIndex);
+		
+		// GpuStaticTableInitializer.EnsureStaticTables(accelerator, kernels, stream);
+
+		_sharedTables = HeuristicGpuCombinedTables.GetStaticTables(acceleratorIndex);
+		DivisorTables = _sharedTables.CreateHeuristicDivisorTables();
+
+		stream.Synchronize();
+		AcceleratorStreamPool.Return(acceleratorIndex, stream); 
+	}
+
+	public void EnsureCapacity(int minCapacity)
+	{
+		if (minCapacity <= BufferCapacity)
+		{
+			return;
+		}
+
+		Input?.Dispose();
+		Output?.Dispose();
+		HeuristicFlag?.Dispose();
+
+		Input = Accelerator.Allocate1D<ulong>(minCapacity);
+		Output = Accelerator.Allocate1D<byte>(minCapacity);
+		HeuristicFlag = Accelerator.Allocate1D<int>(minCapacity);
+
+		BufferCapacity = minCapacity;
+	}
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public void Return() => Return(this);
+
+	public void DisposeResources()
+	{
+		Input?.Dispose();
+		Output?.Dispose();
+		HeuristicFlag?.Dispose();
+		// ReleaseSharedTables(_sharedTables);
+		// These resources are shared between GPU leases
+		// Accelerator.Dispose();
+		// AcceleratorContext.Dispose();
+	}
+}

PerfectNumbers.Core/Gpu/Accelerators/HeuristicGpuCombinedTables.cs

@@ -0,0 +1,69 @@
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu.Accelerators;
+
+internal sealed class HeuristicGpuCombinedTables
+{
+	private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
+
+	private static readonly HeuristicGpuCombinedTables[] _sharedTables = new HeuristicGpuCombinedTables[PerfectNumberConstants.RollingAccelerators];
+
+	internal static void WarmUp(int acceleratorIndex, AcceleratorStream stream) => _sharedTables[acceleratorIndex] = new(_accelerators[acceleratorIndex], stream);
+
+	internal static HeuristicGpuCombinedTables GetStaticTables(int acceleratorIndex) => _sharedTables[acceleratorIndex];
+
+	internal HeuristicGpuCombinedTables(Accelerator accelerator, AcceleratorStream stream)
+	{
+		var combinedEnding1 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding1;
+		HeuristicCombinedDivisorsEnding1 = accelerator.CopySpanToDevice(stream, combinedEnding1);
+		var combinedSquaresEnding1 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding1Squares;
+		HeuristicCombinedDivisorSquaresEnding1 = accelerator.CopySpanToDevice(stream, combinedSquaresEnding1);
+
+		var combinedEnding3 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding3;
+		HeuristicCombinedDivisorsEnding3 = accelerator.CopySpanToDevice(stream, combinedEnding3);
+		var combinedSquaresEnding3 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding3Squares;
+		HeuristicCombinedDivisorSquaresEnding3 = accelerator.CopySpanToDevice(stream, combinedSquaresEnding3);
+
+		var combinedEnding7 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding7;
+		HeuristicCombinedDivisorsEnding7 = accelerator.CopySpanToDevice(stream, combinedEnding7);
+		var combinedSquaresEnding7 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding7Squares;
+		HeuristicCombinedDivisorSquaresEnding7 = accelerator.CopySpanToDevice(stream, combinedSquaresEnding7);
+
+		var combinedEnding9 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding9;
+		HeuristicCombinedDivisorsEnding9 = accelerator.CopySpanToDevice(stream, combinedEnding9);
+		var combinedSquaresEnding9 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding9Squares;
+		HeuristicCombinedDivisorSquaresEnding9 = accelerator.CopySpanToDevice(stream, combinedSquaresEnding9);
+	}
+
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding1;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding1;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding3;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding3;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding7;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding7;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding9;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding9;
+
+	internal HeuristicGpuCombinedDivisorTables CreateHeuristicDivisorTables() => new(
+			HeuristicCombinedDivisorsEnding1.View,
+			HeuristicCombinedDivisorsEnding3.View,
+			HeuristicCombinedDivisorsEnding7.View,
+			HeuristicCombinedDivisorsEnding9.View,
+			HeuristicCombinedDivisorSquaresEnding1.View,
+			HeuristicCombinedDivisorSquaresEnding3.View,
+			HeuristicCombinedDivisorSquaresEnding7.View,
+			HeuristicCombinedDivisorSquaresEnding9.View);
+
+	internal void Dispose()
+	{
+		HeuristicCombinedDivisorsEnding1.Dispose();
+		HeuristicCombinedDivisorSquaresEnding1.Dispose();
+		HeuristicCombinedDivisorsEnding3.Dispose();
+		HeuristicCombinedDivisorSquaresEnding3.Dispose();
+		HeuristicCombinedDivisorsEnding7.Dispose();
+		HeuristicCombinedDivisorSquaresEnding7.Dispose();
+		HeuristicCombinedDivisorsEnding9.Dispose();
+		HeuristicCombinedDivisorSquaresEnding9.Dispose();
+	}
+}

PerfectNumbers.Core/Gpu/Accelerators/HeuristicGpuGroupABTables.cs

@@ -0,0 +1,79 @@
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu.Accelerators;
+
+internal sealed class HeuristicGpuGroupABTables
+{
+	private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
+
+	private static readonly HeuristicGpuGroupABTables[] _sharedTables = new HeuristicGpuGroupABTables[PerfectNumberConstants.RollingAccelerators];
+
+	private static readonly SemaphoreSlim[] _locks = [..Enumerable.Range(1, PerfectNumberConstants.RollingAccelerators).Select(_ => new SemaphoreSlim(1))];
+
+	internal static HeuristicGpuGroupABTables EnsureStaticTables(int acceleratorIndex, AcceleratorStream stream)
+	{
+		var @lock = _locks[acceleratorIndex];
+		@lock.Wait();
+		if (_sharedTables[acceleratorIndex] is {} existing)
+		{
+			@lock.Release();
+			return existing;
+		}
+
+		var accelerator = _accelerators[acceleratorIndex];
+		existing = new(accelerator, stream);
+		_sharedTables[acceleratorIndex] = existing;
+		@lock.Release();
+		return existing;
+	}
+
+	internal HeuristicGpuGroupABTables(Accelerator accelerator, AcceleratorStream stream)
+	{
+		var heuristicGroupA = HeuristicPrimeSieves.GroupADivisorsStorage;
+		HeuristicGroupADivisors = accelerator.CopySpanToDevice(stream, heuristicGroupA);
+
+		var heuristicGroupASquares = HeuristicPrimeSieves.GroupADivisorSquaresStorage;
+		HeuristicGroupADivisorSquares = accelerator.CopySpanToDevice(stream, heuristicGroupASquares);
+
+		HeuristicGroupBDivisorsEnding1 = accelerator.CopyUintSpanToDevice(stream, DivisorGenerator.SmallPrimesLastOneWithoutLastThree);
+		HeuristicGroupBDivisorSquaresEnding1 = accelerator.CopySpanToDevice(stream, DivisorGenerator.SmallPrimesPow2LastOneWithoutLastThree);
+
+		HeuristicGroupBDivisorsEnding7 = accelerator.CopyUintSpanToDevice(stream, DivisorGenerator.SmallPrimesLastSevenWithoutLastThree);
+		HeuristicGroupBDivisorSquaresEnding7 = accelerator.CopySpanToDevice(stream, DivisorGenerator.SmallPrimesPow2LastSevenWithoutLastThree);
+
+		HeuristicGroupBDivisorsEnding9 = accelerator.CopyUintSpanToDevice(stream, DivisorGenerator.SmallPrimesLastNineWithoutLastThree);
+		HeuristicGroupBDivisorSquaresEnding9 = accelerator.CopySpanToDevice(stream, DivisorGenerator.SmallPrimesPow2LastNineWithoutLastThree);
+	}
+
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisors;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisorSquares;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding1;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding1;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding7;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding7;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding9;
+	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding9;
+
+	internal HeuristicGpuGroupABDivisorTables CreateHeuristicDivisorTables() => new(
+			HeuristicGroupADivisors.View,
+			HeuristicGroupADivisorSquares.View,
+			HeuristicGroupBDivisorsEnding1.View,
+			HeuristicGroupBDivisorSquaresEnding1.View,
+			HeuristicGroupBDivisorsEnding7.View,
+			HeuristicGroupBDivisorSquaresEnding7.View,
+			HeuristicGroupBDivisorsEnding9.View,
+			HeuristicGroupBDivisorSquaresEnding9.View);
+
+	internal void Dispose()
+	{
+		HeuristicGroupADivisors.Dispose();
+		HeuristicGroupADivisorSquares.Dispose();
+		HeuristicGroupBDivisorsEnding1.Dispose();
+		HeuristicGroupBDivisorSquaresEnding1.Dispose();
+		HeuristicGroupBDivisorsEnding7.Dispose();
+		HeuristicGroupBDivisorSquaresEnding7.Dispose();
+		HeuristicGroupBDivisorsEnding9.Dispose();
+		HeuristicGroupBDivisorSquaresEnding9.Dispose();
+	}
+}

PerfectNumbers.Core/Gpu/Accelerators/HeuristicGpuTables.cs

@@ -1,150 +0,0 @@
-using ILGPU;
-using ILGPU.Runtime;
-
-namespace PerfectNumbers.Core.Gpu.Accelerators;
-
-internal sealed class HeuristicGpuTables
-{
-	private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
-
-	private static readonly HeuristicGpuTables[] _sharedTables = new HeuristicGpuTables[PerfectNumberConstants.RollingAccelerators];
-
-	private static readonly SemaphoreSlim[] _locks = [..Enumerable.Range(1, PerfectNumberConstants.RollingAccelerators).Select(_ => new SemaphoreSlim(1))];
-
-	internal static HeuristicGpuTables EnsureStaticTables(int acceleratorIndex, AcceleratorStream stream)
-	{
-		var @lock = _locks[acceleratorIndex];
-		@lock.Wait();
-		if (_sharedTables[acceleratorIndex] is {} existing)
-		{
-			@lock.Release();
-			return existing;
-		}
-
-		var accelerator = _accelerators[acceleratorIndex];
-		existing = new(accelerator, stream);
-		_sharedTables[acceleratorIndex] = existing;
-		@lock.Release();
-		return existing;
-	}
-
-	internal HeuristicGpuTables(Accelerator accelerator, AcceleratorStream stream)
-	{
-		var heuristicGroupA = HeuristicPrimeSieves.GroupADivisorsStorage;
-		HeuristicGroupADivisors = CopySpanToDevice(accelerator, stream, heuristicGroupA);
-
-		var heuristicGroupASquares = HeuristicPrimeSieves.GroupADivisorSquaresStorage;
-		HeuristicGroupADivisorSquares = CopySpanToDevice(accelerator, stream, heuristicGroupASquares);
-
-		HeuristicGroupBDivisorsEnding1 = CopyUintSpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesLastOneWithoutLastThree);
-		HeuristicGroupBDivisorSquaresEnding1 = CopySpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesPow2LastOneWithoutLastThree);
-
-		HeuristicGroupBDivisorsEnding7 = CopyUintSpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesLastSevenWithoutLastThree);
-		HeuristicGroupBDivisorSquaresEnding7 = CopySpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesPow2LastSevenWithoutLastThree);
-
-		HeuristicGroupBDivisorsEnding9 = CopyUintSpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesLastNineWithoutLastThree);
-		HeuristicGroupBDivisorSquaresEnding9 = CopySpanToDevice(accelerator, stream, DivisorGenerator.SmallPrimesPow2LastNineWithoutLastThree);
-
-		var combinedEnding1 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding1;
-		HeuristicCombinedDivisorsEnding1 = CopySpanToDevice(accelerator, stream, combinedEnding1);
-		var combinedSquaresEnding1 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding1Squares;
-		HeuristicCombinedDivisorSquaresEnding1 = CopySpanToDevice(accelerator, stream, combinedSquaresEnding1);
-
-		var combinedEnding3 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding3;
-		HeuristicCombinedDivisorsEnding3 = CopySpanToDevice(accelerator, stream, combinedEnding3);
-		var combinedSquaresEnding3 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding3Squares;
-		HeuristicCombinedDivisorSquaresEnding3 = CopySpanToDevice(accelerator, stream, combinedSquaresEnding3);
-
-		var combinedEnding7 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding7;
-		HeuristicCombinedDivisorsEnding7 = CopySpanToDevice(accelerator, stream, combinedEnding7);
-		var combinedSquaresEnding7 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding7Squares;
-		HeuristicCombinedDivisorSquaresEnding7 = CopySpanToDevice(accelerator, stream, combinedSquaresEnding7);
-
-		var combinedEnding9 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding9;
-		HeuristicCombinedDivisorsEnding9 = CopySpanToDevice(accelerator, stream, combinedEnding9);
-		var combinedSquaresEnding9 = HeuristicCombinedPrimeTester.CombinedDivisorsEnding9Squares;
-		HeuristicCombinedDivisorSquaresEnding9 = CopySpanToDevice(accelerator, stream, combinedSquaresEnding9);
-	}
-
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisors;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisorSquares;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding1;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding1;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding7;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding7;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding9;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding9;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding1;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding1;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding3;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding3;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding7;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding7;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding9;
-	internal readonly MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding9;
-
-	internal HeuristicGpuDivisorTables CreateHeuristicDivisorTables() => new(
-			HeuristicCombinedDivisorsEnding1.View,
-			HeuristicCombinedDivisorsEnding3.View,
-			HeuristicCombinedDivisorsEnding7.View,
-			HeuristicCombinedDivisorsEnding9.View,
-			HeuristicCombinedDivisorSquaresEnding1.View,
-			HeuristicCombinedDivisorSquaresEnding3.View,
-			HeuristicCombinedDivisorSquaresEnding7.View,
-			HeuristicCombinedDivisorSquaresEnding9.View,
-			HeuristicGroupADivisors.View,
-			HeuristicGroupADivisorSquares.View,
-			HeuristicGroupBDivisorsEnding1.View,
-			HeuristicGroupBDivisorSquaresEnding1.View,
-			HeuristicGroupBDivisorsEnding7.View,
-			HeuristicGroupBDivisorSquaresEnding7.View,
-			HeuristicGroupBDivisorsEnding9.View,
-			HeuristicGroupBDivisorSquaresEnding9.View);
-
-	private static MemoryBuffer1D<ulong, Stride1D.Dense> CopySpanToDevice(Accelerator accelerator, AcceleratorStream stream, in ulong[] span)
-	{
-		MemoryBuffer1D<ulong, Stride1D.Dense>? buffer;
-		buffer = accelerator.Allocate1D(stream, span);
-
-		return buffer;
-	}
-
-	private static MemoryBuffer1D<ulong, Stride1D.Dense> CopyUintSpanToDevice(Accelerator accelerator, AcceleratorStream stream, ReadOnlySpan<uint> span)
-	{
-		MemoryBuffer1D<ulong, Stride1D.Dense>? buffer;
-		buffer = accelerator.Allocate1D<ulong>(span.Length);
-
-		if (!span.IsEmpty)
-		{
-			var converted = new ulong[span.Length];
-			for (int i = 0; i < span.Length; i++)
-			{
-				converted[i] = span[i];
-			}
-
-			buffer.View.CopyFromCPU(stream, converted);
-		}
-
-		return buffer;
-	}
-
-	internal void Dispose()
-	{
-		HeuristicGroupADivisors.Dispose();
-		HeuristicGroupADivisorSquares.Dispose();
-		HeuristicGroupBDivisorsEnding1.Dispose();
-		HeuristicGroupBDivisorSquaresEnding1.Dispose();
-		HeuristicGroupBDivisorsEnding7.Dispose();
-		HeuristicGroupBDivisorSquaresEnding7.Dispose();
-		HeuristicGroupBDivisorsEnding9.Dispose();
-		HeuristicGroupBDivisorSquaresEnding9.Dispose();
-		HeuristicCombinedDivisorsEnding1.Dispose();
-		HeuristicCombinedDivisorSquaresEnding1.Dispose();
-		HeuristicCombinedDivisorsEnding3.Dispose();
-		HeuristicCombinedDivisorSquaresEnding3.Dispose();
-		HeuristicCombinedDivisorsEnding7.Dispose();
-		HeuristicCombinedDivisorSquaresEnding7.Dispose();
-		HeuristicCombinedDivisorsEnding9.Dispose();
-		HeuristicCombinedDivisorSquaresEnding9.Dispose();
-	}
-}

PerfectNumbers.Core/Gpu/Accelerators/HeuristicGroupABPrimeTesterAccelerator.cs

@@ -1,15 +1,14 @@
-using System.Runtime.CompilerServices;
 using ILGPU;
 using ILGPU.Runtime;
 
 namespace PerfectNumbers.Core.Gpu.Accelerators;
 
-internal sealed class HeuristicPrimeTesterAccelerator
+internal sealed class HeuristicGroupABPrimeTesterAccelerator
 {
 	#region Pool
 
 	[ThreadStatic]
-	private static Queue<HeuristicPrimeTesterAccelerator>? Pool;
+	private static Queue<HeuristicGroupABPrimeTesterAccelerator>? Pool;
 
 	internal static void WarmUp()
 	{
@@ -20,23 +19,22 @@ internal sealed class HeuristicPrimeTesterAccelerator
 			Console.WriteLine($"Preparing heuristic accelerator {i}...");
 			var accelerator = accelerators[i];
 			AcceleratorStream stream = accelerator.CreateStream();
-			Accelerators.HeuristicGpuTables.EnsureStaticTables(i, stream);
+			_ = HeuristicGpuGroupABTables.EnsureStaticTables(i, stream);
 			// _ = GpuKernelPool.GetOrAddKernels(accelerator, stream, KernelType.None);
 			// KernelContainer kernels = GpuKernelPool.GetOrAddKernels(accelerator, stream);
 			// GpuStaticTableInitializer.EnsureStaticTables(accelerator, kernels, stream);
 			stream.Synchronize();
 			stream.Dispose();
-			accelerator.Synchronize();
 			Console.WriteLine($"Heuristic accelerator {i} is ready");
 		}
 	}
 
-	internal static HeuristicPrimeTesterAccelerator Rent(int minBufferCapacity = 1)
+	internal static HeuristicGroupABPrimeTesterAccelerator Rent(int minBufferCapacity = 1)
 	{
 		var pool = Pool ??= new();
 		if (!pool.TryDequeue(out var lease))
 		{
-			lease = new HeuristicPrimeTesterAccelerator(minBufferCapacity);
+			lease = new HeuristicGroupABPrimeTesterAccelerator(minBufferCapacity);
 		}
 		else
 		{
@@ -46,7 +44,7 @@ internal sealed class HeuristicPrimeTesterAccelerator
 		return lease;
 	}
 
-	internal static void Return(HeuristicPrimeTesterAccelerator lease)
+	internal static void Return(HeuristicGroupABPrimeTesterAccelerator lease)
 	{
 		var pool = Pool ??= new();
 		pool.Enqueue(lease);
@@ -67,7 +65,7 @@ internal sealed class HeuristicPrimeTesterAccelerator
 	{
 		if (Pool != null)
 		{
-			var retained = new List<HeuristicPrimeTesterAccelerator>();
+			var retained = new List<HeuristicGroupABPrimeTesterAccelerator>();
 			while (Pool.TryDequeue(out var lease))
 			{
 				lease.DisposeResources();
@@ -77,10 +75,9 @@ internal sealed class HeuristicPrimeTesterAccelerator
 
 	#endregion
 
-	private readonly HeuristicGpuDivisorTables _heuristicDivisorTables;
+	public readonly HeuristicGpuGroupABDivisorTables DivisorTables;
 	internal readonly Context Context;
 	public readonly Accelerator Accelerator;
-	public AcceleratorStream? Stream;
 
 	[ThreadStatic]
 	public static Dictionary<Accelerator, Action<AcceleratorStream, Index1D, ArrayView<ulong>, ArrayView<uint>, ArrayView<uint>, ArrayView<uint>, ArrayView<uint>, ArrayView<ulong>, ArrayView<ulong>, ArrayView<ulong>, ArrayView<ulong>, ArrayView<byte>>>? SmallPrimeSieveKernel;
@@ -100,12 +97,12 @@ internal sealed class HeuristicPrimeTesterAccelerator
 
 	public readonly Kernel HeuristicTrialDivisionKernel;
 
-	public MemoryBuffer1D<ulong, Stride1D.Dense> Input = null!;
-	public MemoryBuffer1D<byte, Stride1D.Dense> Output = null!;
-	public MemoryBuffer1D<int, Stride1D.Dense> HeuristicFlag = null!;
+	public MemoryBuffer1D<ulong, Stride1D.Dense>? Input = null;
+	public MemoryBuffer1D<byte, Stride1D.Dense>? Output = null;
+	public MemoryBuffer1D<int, Stride1D.Dense>? HeuristicFlag = null!;
 	public int BufferCapacity;
 
-	private HeuristicGpuTables _sharedTables;
+	private HeuristicGpuGroupABTables _sharedTables;
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisors => _sharedTables.HeuristicGroupADivisors;
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupADivisorSquares => _sharedTables.HeuristicGroupADivisorSquares;
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding1 => _sharedTables.HeuristicGroupBDivisorsEnding1;
@@ -114,36 +111,28 @@ internal sealed class HeuristicPrimeTesterAccelerator
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding7 => _sharedTables.HeuristicGroupBDivisorSquaresEnding7;
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorsEnding9 => _sharedTables.HeuristicGroupBDivisorsEnding9;
 	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicGroupBDivisorSquaresEnding9 => _sharedTables.HeuristicGroupBDivisorSquaresEnding9;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding1 => _sharedTables.HeuristicCombinedDivisorsEnding1;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding1 => _sharedTables.HeuristicCombinedDivisorSquaresEnding1;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding3 => _sharedTables.HeuristicCombinedDivisorsEnding3;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding3 => _sharedTables.HeuristicCombinedDivisorSquaresEnding3;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding7 => _sharedTables.HeuristicCombinedDivisorsEnding7;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding7 => _sharedTables.HeuristicCombinedDivisorSquaresEnding7;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorsEnding9 => _sharedTables.HeuristicCombinedDivisorsEnding9;
-	public MemoryBuffer1D<ulong, Stride1D.Dense> HeuristicCombinedDivisorSquaresEnding9 => _sharedTables.HeuristicCombinedDivisorSquaresEnding9;
-
-	public HeuristicGpuDivisorTables HeuristicGpuTables => _heuristicDivisorTables;
 
 	private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
+	internal readonly int AcceleratorIndex;
 
-	internal HeuristicPrimeTesterAccelerator(int minBufferCapacity)
+	internal HeuristicGroupABPrimeTesterAccelerator(int minBufferCapacity)
 	{
 		var acceleratorIndex = AcceleratorPool.Shared.Rent();
+		AcceleratorIndex = acceleratorIndex;
 		Accelerator accelerator = _accelerators[acceleratorIndex];
 		Context = accelerator.Context;
 
 		Accelerator = accelerator;
 		EnsureCapacity(minBufferCapacity);
 
-		HeuristicTrialDivisionKernel = KernelUtil.GetKernel(accelerator.LoadAutoGroupedStreamKernel<Index1D, ArrayView<int>, ulong, ulong, HeuristicGpuDivisorTableKind, HeuristicGpuDivisorTables>(PrimeTesterKernels.HeuristicTrialDivisionKernel));
+		HeuristicTrialDivisionKernel = KernelUtil.GetKernel(accelerator.LoadAutoGroupedStreamKernel<Index1D, ArrayView<int>, ulong, ulong, HeuristicGpuDivisorTableKind, HeuristicGpuGroupABDivisorTables>(PrimeTesterKernels.HeuristicTrialGroupABDivisionKernel));
 
 		AcceleratorStream stream = AcceleratorStreamPool.Rent(acceleratorIndex);
 		
 		// GpuStaticTableInitializer.EnsureStaticTables(accelerator, kernels, stream);
 
-		_sharedTables = Accelerators.HeuristicGpuTables.EnsureStaticTables(acceleratorIndex, stream);
-		_heuristicDivisorTables = _sharedTables.CreateHeuristicDivisorTables();
+		_sharedTables = HeuristicGpuGroupABTables.EnsureStaticTables(acceleratorIndex, stream);
+		DivisorTables = _sharedTables.CreateHeuristicDivisorTables();
 
 		stream.Synchronize();
 		AcceleratorStreamPool.Return(acceleratorIndex, stream); 
@@ -156,8 +145,8 @@ internal sealed class HeuristicPrimeTesterAccelerator
 			return;
 		}
 
-		Input.Dispose();
-		Output.Dispose();
+		Input?.Dispose();
+		Output?.Dispose();
 		HeuristicFlag?.Dispose();
 
 		Input = Accelerator.Allocate1D<ulong>(minCapacity);
@@ -169,8 +158,6 @@ internal sealed class HeuristicPrimeTesterAccelerator
 
 	public void Dispose()
 	{
-		Stream?.Dispose();
-		Stream = null;
 		Return(this);
 	}
 
@@ -179,8 +166,6 @@ internal sealed class HeuristicPrimeTesterAccelerator
 		Input?.Dispose();
 		Output?.Dispose();
 		HeuristicFlag?.Dispose();
-		Stream?.Dispose();
-		Stream = null;
 		// ReleaseSharedTables(_sharedTables);
 		// These resources are shared between GPU leases
 		// Accelerator.Dispose();

PerfectNumbers.Core/Gpu/Accelerators/PrimeOrderCalculatorAccelerator.cs

@@ -68,6 +68,7 @@ public sealed class PrimeOrderCalculatorAccelerator
 			// Don't take this from the pool as quick uploads of data to the accelerator consumes much of GPU's memory and throws.
 			AcceleratorStream stream = accelerator.CreateStream();
 			LastDigitGpuTables.WarmUp(i, stream);
+			HeuristicCombinedPrimeTesterAccelerator.WarmUp(i, stream);
 			// SharedHeuristicGpuTables.EnsureStaticTables(accelerator, stream);
 			// _ = GpuKernelPool.GetOrAddKernels(accelerator, stream, KernelType.None);
 			// KernelContainer kernels = GpuKernelPool.GetOrAddKernels(accelerator, stream);
@@ -76,6 +77,7 @@ public sealed class PrimeOrderCalculatorAccelerator
 			stream.Dispose();
 			accelerator.Synchronize();
 		}
+
 	}
 
 	#endregion

PerfectNumbers.Core/Gpu/HeuristicGpuCombinedDivisorTables.cs

@@ -0,0 +1,45 @@
+using System.Runtime.CompilerServices;
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu;
+
+public readonly struct HeuristicGpuCombinedDivisorTables(
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding1,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding3,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding7,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding9,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding1,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding3,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding7,
+		ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding9)
+{
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding1 = combinedDivisorsEnding1;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding3 = combinedDivisorsEnding3;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding7 = combinedDivisorsEnding7;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding9 = combinedDivisorsEnding9;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding1 = combinedDivisorSquaresEnding1;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding3 = combinedDivisorSquaresEnding3;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding7 = combinedDivisorSquaresEnding7;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding9 = combinedDivisorSquaresEnding9;
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisors(byte ending) => ending switch
+	{
+		1 => CombinedDivisorsEnding1,
+		3 => CombinedDivisorsEnding3,
+		7 => CombinedDivisorsEnding7,
+		9 => CombinedDivisorsEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisorSquares(byte ending) => ending switch
+	{
+		1 => CombinedDivisorSquaresEnding1,
+		3 => CombinedDivisorSquaresEnding3,
+		7 => CombinedDivisorSquaresEnding7,
+		9 => CombinedDivisorSquaresEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+}

PerfectNumbers.Core/Gpu/HeuristicGpuDivisorTables.cs

@@ -1,139 +0,0 @@
-using System.Runtime.CompilerServices;
-using ILGPU;
-using ILGPU.Runtime;
-
-namespace PerfectNumbers.Core.Gpu;
-
-public readonly struct HeuristicGpuDivisorTables
-{
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding1;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding3;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding7;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorsEnding9;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding1;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding3;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding7;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> CombinedDivisorSquaresEnding9;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupADivisors;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupADivisorSquares;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding1;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding1;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding7;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding7;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding9;
-	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding9;
-
-	public HeuristicGpuDivisorTables(
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding1,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding3,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding7,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorsEnding9,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding1,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding3,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding7,
-			ArrayView1D<ulong, Stride1D.Dense> combinedDivisorSquaresEnding9,
-			ArrayView1D<ulong, Stride1D.Dense> groupADivisors,
-			ArrayView1D<ulong, Stride1D.Dense> groupADivisorSquares,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding1,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding1,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding7,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding7,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding9,
-			ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding9)
-	{
-		CombinedDivisorsEnding1 = combinedDivisorsEnding1;
-		CombinedDivisorsEnding3 = combinedDivisorsEnding3;
-		CombinedDivisorsEnding7 = combinedDivisorsEnding7;
-		CombinedDivisorsEnding9 = combinedDivisorsEnding9;
-		CombinedDivisorSquaresEnding1 = combinedDivisorSquaresEnding1;
-		CombinedDivisorSquaresEnding3 = combinedDivisorSquaresEnding3;
-		CombinedDivisorSquaresEnding7 = combinedDivisorSquaresEnding7;
-		CombinedDivisorSquaresEnding9 = combinedDivisorSquaresEnding9;
-		GroupADivisors = groupADivisors;
-		GroupADivisorSquares = groupADivisorSquares;
-		GroupBDivisorsEnding1 = groupBDivisorsEnding1;
-		GroupBDivisorSquaresEnding1 = groupBDivisorSquaresEnding1;
-		GroupBDivisorsEnding7 = groupBDivisorsEnding7;
-		GroupBDivisorSquaresEnding7 = groupBDivisorSquaresEnding7;
-		GroupBDivisorsEnding9 = groupBDivisorsEnding9;
-		GroupBDivisorSquaresEnding9 = groupBDivisorSquaresEnding9;
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectCombined(byte ending)
-	{
-		return ending switch
-		{
-			1 => CombinedDivisorsEnding1,
-			3 => CombinedDivisorsEnding3,
-			7 => CombinedDivisorsEnding7,
-			9 => CombinedDivisorsEnding9,
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectCombinedSquares(byte ending)
-	{
-		return ending switch
-		{
-			1 => CombinedDivisorSquaresEnding1,
-			3 => CombinedDivisorSquaresEnding3,
-			7 => CombinedDivisorSquaresEnding7,
-			9 => CombinedDivisorSquaresEnding9,
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectGroupB(byte ending)
-	{
-		return ending switch
-		{
-			1 => GroupBDivisorsEnding1,
-			7 => GroupBDivisorsEnding7,
-			9 => GroupBDivisorsEnding9,
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectGroupBSquares(byte ending)
-	{
-		return ending switch
-		{
-			1 => GroupBDivisorSquaresEnding1,
-			7 => GroupBDivisorSquaresEnding7,
-			9 => GroupBDivisorSquaresEnding9,
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisors(HeuristicGpuDivisorTableKind kind, byte ending)
-	{
-		return kind switch
-		{
-			HeuristicGpuDivisorTableKind.GroupA => GroupADivisors,
-			HeuristicGpuDivisorTableKind.GroupBEnding1 => GroupBDivisorsEnding1,
-			HeuristicGpuDivisorTableKind.GroupBEnding7 => GroupBDivisorsEnding7,
-			HeuristicGpuDivisorTableKind.GroupBEnding9 => GroupBDivisorsEnding9,
-			HeuristicGpuDivisorTableKind.Combined => SelectCombined(ending),
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-
-	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisorSquares(HeuristicGpuDivisorTableKind kind, byte ending)
-	{
-		return kind switch
-		{
-			HeuristicGpuDivisorTableKind.GroupA => GroupADivisorSquares,
-			HeuristicGpuDivisorTableKind.GroupBEnding1 => GroupBDivisorSquaresEnding1,
-			HeuristicGpuDivisorTableKind.GroupBEnding7 => GroupBDivisorSquaresEnding7,
-			HeuristicGpuDivisorTableKind.GroupBEnding9 => GroupBDivisorSquaresEnding9,
-			HeuristicGpuDivisorTableKind.Combined => SelectCombinedSquares(ending),
-			_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
-		};
-	}
-}

PerfectNumbers.Core/Gpu/HeuristicGpuGroupABDivisorTables.cs

@@ -0,0 +1,63 @@
+using System.Runtime.CompilerServices;
+using ILGPU;
+using ILGPU.Runtime;
+
+namespace PerfectNumbers.Core.Gpu;
+
+public readonly struct HeuristicGpuGroupABDivisorTables(
+		ArrayView1D<ulong, Stride1D.Dense> groupADivisors,
+		ArrayView1D<ulong, Stride1D.Dense> groupADivisorSquares,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding1,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding1,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding7,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding7,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorsEnding9,
+		ArrayView1D<ulong, Stride1D.Dense> groupBDivisorSquaresEnding9)
+{
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupADivisors = groupADivisors;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupADivisorSquares = groupADivisorSquares;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding1 = groupBDivisorsEnding1;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding1 = groupBDivisorSquaresEnding1;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding7 = groupBDivisorsEnding7;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding7 = groupBDivisorSquaresEnding7;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorsEnding9 = groupBDivisorsEnding9;
+	public readonly ArrayView1D<ulong, Stride1D.Dense> GroupBDivisorSquaresEnding9 = groupBDivisorSquaresEnding9;
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectGroupB(byte ending) => ending switch
+	{
+		1 => GroupBDivisorsEnding1,
+		7 => GroupBDivisorsEnding7,
+		9 => GroupBDivisorsEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectGroupBSquares(byte ending) => ending switch
+	{
+		1 => GroupBDivisorSquaresEnding1,
+		7 => GroupBDivisorSquaresEnding7,
+		9 => GroupBDivisorSquaresEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisors(HeuristicGpuDivisorTableKind kind) => kind switch
+	{
+		HeuristicGpuDivisorTableKind.GroupA => GroupADivisors,
+		HeuristicGpuDivisorTableKind.GroupBEnding1 => GroupBDivisorsEnding1,
+		HeuristicGpuDivisorTableKind.GroupBEnding7 => GroupBDivisorsEnding7,
+		HeuristicGpuDivisorTableKind.GroupBEnding9 => GroupBDivisorsEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
+	public ArrayView1D<ulong, Stride1D.Dense> SelectDivisorSquares(HeuristicGpuDivisorTableKind kind) => kind switch
+	{
+		HeuristicGpuDivisorTableKind.GroupA => GroupADivisorSquares,
+		HeuristicGpuDivisorTableKind.GroupBEnding1 => GroupBDivisorSquaresEnding1,
+		HeuristicGpuDivisorTableKind.GroupBEnding7 => GroupBDivisorSquaresEnding7,
+		HeuristicGpuDivisorTableKind.GroupBEnding9 => GroupBDivisorSquaresEnding9,
+		_ => ArrayView1D<ulong, Stride1D.Dense>.Empty,
+	};
+}

PerfectNumbers.Core/Gpu/Kernels/PrimeTesterKernels.cs

@@ -11,7 +11,6 @@ public enum HeuristicGpuDivisorTableKind : byte
     GroupBEnding1 = 1,
     GroupBEnding7 = 7,
     GroupBEnding9 = 9,
-    Combined = 255,
 }
 
 internal static class PrimeTesterKernels
@@ -78,17 +77,49 @@ internal static class PrimeTesterKernels
         results[index] = result;
     }
 
-    public static void HeuristicTrialDivisionKernel(
+    public static void HeuristicTrialCombinedDivisionKernel(
+        Index1D index,
+		byte nMod10,
+        ArrayView<int> resultFlag,
+        ulong n,
+        ulong maxDivisorSquare,
+        HeuristicGpuCombinedDivisorTables tables)
+    {
+        // byte nMod10 = (byte)(n % 10UL);
+        ArrayView1D<ulong, Stride1D.Dense> divisors = tables.SelectDivisors(nMod10);
+        ArrayView1D<ulong, Stride1D.Dense> divisorSquares = tables.SelectDivisorSquares(nMod10);
+
+        int divisorLength = (int)divisorSquares.Length;
+        int threadIndex = index;
+        if (threadIndex >= divisorLength)
+        {
+            return;
+        }
+
+        ulong divisorSquare = divisorSquares[threadIndex];
+        if (divisorSquare > maxDivisorSquare)
+        {
+            return;
+        }
+
+        ulong divisor = divisors[threadIndex];
+        divisor = n % divisor;
+        if (divisor == 0UL)
+        {
+            resultFlag[0] = 1;
+        }
+    }
+
+    public static void HeuristicTrialGroupABDivisionKernel(
         Index1D index,
         ArrayView<int> resultFlag,
         ulong n,
         ulong maxDivisorSquare,
         HeuristicGpuDivisorTableKind tableKind,
-        HeuristicGpuDivisorTables tables)
+        HeuristicGpuGroupABDivisorTables tables)
     {
-        byte nMod10 = (byte)(n % 10UL);
-        ArrayView1D<ulong, Stride1D.Dense> divisors = tables.SelectDivisors(tableKind, nMod10);
-        ArrayView1D<ulong, Stride1D.Dense> divisorSquares = tables.SelectDivisorSquares(tableKind, nMod10);
+        ArrayView1D<ulong, Stride1D.Dense> divisors = tables.SelectDivisors(tableKind);
+        ArrayView1D<ulong, Stride1D.Dense> divisorSquares = tables.SelectDivisorSquares(tableKind);
 
         int divisorLength = (int)divisorSquares.Length;
         int threadIndex = index;

PerfectNumbers.Core/Gpu/MersenneNumberDivisorByDivisorGpuTester.cs

@@ -8,6 +8,7 @@ using System.Threading;
 using PerfectNumbers.Core;
 using ILGPU;
 using ILGPU.Runtime;
+using PerfectNumbers.Core.Gpu.Accelerators;
 
 namespace PerfectNumbers.Core.Gpu;
 
@@ -106,9 +107,12 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 		ulong lastProcessed;
 
 		// GpuPrimeWorkLimiter();
-		int acceleratorIndex = AcceleratorPool.Shared.Rent();
-		var accelerator = _accelerators[acceleratorIndex];
-		var stream = accelerator.CreateStream();
+		// int acceleratorIndex = AcceleratorPool.Shared.Rent();
+		// var accelerator = _accelerators[acceleratorIndex];
+		var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(batchCapacity);
+		var acceleratorIndex = gpu.AcceleratorIndex;
+		var accelerator = gpu.Accelerator;
+		var stream = AcceleratorStreamPool.Rent(acceleratorIndex);
 
 		// Monitor.Enter(gpuLease.ExecutionLock);
 
@@ -116,6 +120,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 		var resources = RentBatchResources(accelerator, batchCapacity);
 
 		composite = CheckDivisors(
+			gpu,
 			prime,
 			allowedMax,
 			kernel,
@@ -137,8 +142,9 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 			out coveredRange,
 			out processedCount);
 
-		stream.Dispose();
+		AcceleratorStreamPool.Return(acceleratorIndex, stream);
 		ReturnBatchResources(resources);
+		HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 		// Monitor.Exit(gpuLease.ExecutionLock);
 		// GpuPrimeWorkLimiter.Release();
 
@@ -182,6 +188,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 	}
 
 	private static bool CheckDivisors(
+		HeuristicCombinedPrimeTesterAccelerator gpu,
 		ulong prime,
 		ulong allowedMax,
 		Action<AcceleratorStream, Index1D, ArrayView<GpuDivisorPartialData>, ArrayView<int>, ArrayView<int>, ArrayView<ulong>, ArrayView<ulong>, ArrayView<byte>, ArrayView<int>> kernel,
@@ -205,7 +212,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 	{
 		int batchCapacity = (int)divisorDataBuffer.Length;
 		bool composite = false;
-		bool processedAll = false;
+		bool processedAll;
 		processedCount = 0UL;
 		lastProcessed = 0UL;
 
@@ -303,7 +310,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 				{
 					ulong divisorValue = (ulong)nextDivisor128;
 					MontgomeryDivisorData montgomeryData = MontgomeryDivisorData.FromModulus(divisorValue);
-					ulong divisorCycle = ResolveDivisorCycle(divisorValue, prime, in montgomeryData);
+					ulong divisorCycle = ResolveDivisorCycle(gpu, divisorValue, prime, in montgomeryData);
 					if (divisorCycle == prime)
 					{
 						processedCount += (ulong)(i + 1);
@@ -375,9 +382,9 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 
 
 	[MethodImpl(MethodImplOptions.AggressiveInlining)]
-	private static ulong ResolveDivisorCycle(ulong divisor, ulong prime, in MontgomeryDivisorData divisorData)
+	private static ulong ResolveDivisorCycle(HeuristicCombinedPrimeTesterAccelerator gpu, ulong divisor, ulong prime, in MontgomeryDivisorData divisorData)
 	{
-		if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(divisor, prime, divisorData, out ulong computedCycle, out bool primeOrderFailed) || computedCycle == 0UL)
+		if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(gpu, divisor, prime, divisorData, out ulong computedCycle, out bool primeOrderFailed) || computedCycle == 0UL)
 		{
 			return MersenneDivisorCycles.CalculateCycleLength(divisor, divisorData, skipPrimeOrderHeuristic: primeOrderFailed);
 		}
@@ -498,6 +505,7 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 		private static readonly Accelerator[] _accelerators = AcceleratorPool.Shared.Accelerators;
 
 		private readonly MersenneNumberDivisorByDivisorGpuTester _owner;
+		private readonly HeuristicCombinedPrimeTesterAccelerator _primeTesterAccelerator;
 		private readonly Accelerator _accelerator;
 		private readonly AcceleratorStream _stream;
 		private Action<AcceleratorStream, Index1D, ArrayView<GpuDivisorPartialData>, ArrayView<int>, ArrayView<int>, ArrayView<ulong>, ArrayView<ulong>, ArrayView<byte>, ArrayView<int>> _kernel = null!;
@@ -516,8 +524,8 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 		{
 			_owner = owner;
 			// GpuPrimeWorkLimiter.Acquire();
-			int acceleratorIndex = AcceleratorPool.Shared.Rent();
-			Accelerator accelerator = _accelerators[acceleratorIndex];
+			_primeTesterAccelerator = HeuristicCombinedPrimeTesterAccelerator.Rent();
+			Accelerator accelerator = _primeTesterAccelerator.Accelerator;
 			_accelerator = accelerator;
 			_stream = accelerator.CreateStream();
 			_capacity = Math.Max(1, owner._gpuBatchSize);
@@ -600,7 +608,8 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 
 			if (cycle == 0UL)
 			{
-				if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(divisor, firstPrime, divisorData, out ulong computedCycle, out bool primeOrderFailed) || computedCycle == 0UL)
+				var gpu = _primeTesterAccelerator;
+				if (!MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(gpu, divisor, firstPrime, divisorData, out ulong computedCycle, out bool primeOrderFailed) || computedCycle == 0UL)
 				{
 					cycle = MersenneDivisorCycles.CalculateCycleLength(divisor, divisorData, skipPrimeOrderHeuristic: primeOrderFailed);
 				}
@@ -657,10 +666,11 @@ public sealed class MersenneNumberDivisorByDivisorGpuTester : IMersenneNumberDiv
 			ref byte hitRef = ref MemoryMarshal.GetReference(hitSlice);
 			hitView.CopyToCPU(stream, ref hitRef, length);
 			stream.Synchronize();
+
 			// Monitor.Exit(_lease.ExecutionLock);
 		}
 
-		public void Dispose()
+		public void Return()
 		{
 			_owner._sessionPool.Add(this);
 		}

PerfectNumbers.Core/HeuristicCombinedPrimeTester.cs

@@ -3,6 +3,7 @@ using ILGPU.Runtime;
 using System.Runtime.CompilerServices;
 using PerfectNumbers.Core.Gpu;
 using PerfectNumbers.Core.Gpu.Accelerators;
+using ILGPU;
 
 namespace PerfectNumbers.Core;
 
@@ -172,10 +173,20 @@ public sealed class HeuristicCombinedPrimeTester
 	{
 		byte nMod10 = (byte)n.Mod10();
 		ulong maxDivisorSquare = ComputeHeuristicDivisorSquareLimit(n);
-		return IsPrimeGpu(n, maxDivisorSquare, nMod10);
+		var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
+		bool isPrime = IsPrimeGpu(gpu, n, maxDivisorSquare, nMod10);
+		HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
+		return isPrime;
 	}
 
-	public static bool IsPrimeGpu(ulong n, ulong maxDivisorSquare, byte nMod10)
+	public static bool IsPrimeGpu(HeuristicCombinedPrimeTesterAccelerator gpu, ulong n)
+	{
+		byte nMod10 = (byte)n.Mod10();
+		ulong maxDivisorSquare = ComputeHeuristicDivisorSquareLimit(n);
+		return IsPrimeGpu(gpu, n, maxDivisorSquare, nMod10);
+	}
+
+	public static bool IsPrimeGpu(HeuristicCombinedPrimeTesterAccelerator gpu, ulong n, ulong maxDivisorSquare, byte nMod10)
 	{
 		// TODO: Is this condition ever met on the execution path in EvenPerfectBitScanner?
 		if (maxDivisorSquare < 9UL)
@@ -183,7 +194,7 @@ public sealed class HeuristicCombinedPrimeTester
 			return EvaluateWithOpenNumericFallback(n);
 		}
 
-		bool compositeDetected = HeuristicTrialDivisionGpuDetectsDivisor(n, maxDivisorSquare, nMod10);
+		bool compositeDetected = HeuristicTrialDivisionGpuDetectsDivisor(gpu, n, maxDivisorSquare, nMod10);
 		return !compositeDetected;
 	}
 
@@ -222,40 +233,38 @@ public sealed class HeuristicCombinedPrimeTester
 	};
 
 
-	private static bool HeuristicTrialDivisionGpuDetectsDivisor(ulong n, ulong maxDivisorSquare, byte nMod10)
+	private static bool HeuristicTrialDivisionGpuDetectsDivisor(HeuristicCombinedPrimeTesterAccelerator gpu, ulong n, ulong maxDivisorSquare, byte nMod10)
 	{
 		// GpuPrimeWorkLimiter.Acquire();
-		var gpu = HeuristicPrimeTesterAccelerator.Rent(1);
-		var accelerator = gpu.Accelerator;
-		var stream = gpu.Stream;
-		var kernel = gpu.HeuristicTrialDivisionKernel;
-		var flagView1D = gpu.HeuristicFlag.View;
-		var flagView = flagView1D.AsContiguous();
+		// var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
+		var acceleratorIndex = gpu.AcceleratorIndex;
+		var stream = AcceleratorStreamPool.Rent(acceleratorIndex);
+		var kernel = gpu.HeuristicCombinedTrialDivisionKernel;
+		var flagView1D = gpu.HeuristicFlag!.View;
 
 		bool compositeDetected = false;
 		int divisorLength = GetCombinedDivisors(nMod10).Length;
 
 		int compositeFlag = 0;
 		flagView1D.CopyFromCPU(stream, ref compositeFlag, 1);
-		stream!.Synchronize();
 
-
-		kernel.Launch(
+		var kernelLauncher = kernel.CreateLauncherDelegate<Action<AcceleratorStream, Index1D, byte, ArrayView<int>, ulong, ulong, HeuristicGpuCombinedDivisorTables>>();		
+		kernelLauncher(
 				stream,
 				1,
-				divisorLength,
-				flagView,
+				nMod10,
+				flagView1D,
 				n,
 				maxDivisorSquare,
-				HeuristicGpuDivisorTableKind.Combined,
-				gpu.HeuristicGpuTables);
+				gpu.DivisorTables);
 		flagView1D.CopyToCPU(stream, ref compositeFlag, 1);
 		stream.Synchronize();
 
+		AcceleratorStreamPool.Return(acceleratorIndex, stream);
 		// GpuPrimeWorkLimiter.Release();
 
 		compositeDetected = compositeFlag != 0;
-		HeuristicPrimeTesterAccelerator.Return(gpu);
+		HeuristicCombinedPrimeTesterAccelerator.Return(gpu);
 		return compositeDetected;
 	}
 
@@ -490,6 +499,7 @@ public sealed class HeuristicCombinedPrimeTester
 
 	[MethodImpl(MethodImplOptions.AggressiveInlining)]
 	internal static ulong ResolveHeuristicCycleLength(
+		HeuristicCombinedPrimeTesterAccelerator gpu,
 		ulong exponent,
 		in HeuristicDivisorPreparation preparation,
 		out bool cycleFromHint,
@@ -508,6 +518,7 @@ public sealed class HeuristicCombinedPrimeTester
 		MontgomeryDivisorData divisorData = preparation.DivisorData;
 
 		bool trySuccess = MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
+			gpu,
 			divisor,
 			exponent,
 			divisorData,

PerfectNumbers.Core/HeuristicPrimeTester.cs

@@ -3,6 +3,7 @@ using System.Runtime.CompilerServices;
 using ILGPU.Runtime;
 using PerfectNumbers.Core.Gpu;
 using PerfectNumbers.Core.Gpu.Accelerators;
+using ILGPU;
 
 namespace PerfectNumbers.Core;
 
@@ -242,72 +243,80 @@ public sealed class HeuristicPrimeTester
 	private bool HeuristicTrialDivisionGpuDetectsDivisor(ulong n, ulong maxDivisorSquare, byte nMod10)
 	{
 		// GpuPrimeWorkLimiter.Acquire();
-		var gpu = HeuristicPrimeTesterAccelerator.Rent(1);
-		var stream = gpu.Stream;
-		var kernel = gpu.HeuristicTrialDivisionKernel;
-		var flagView1D = gpu.HeuristicFlag.View;
-		var flagView = flagView1D.AsContiguous();
+		var gpu = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
+		int acceleratorIndex = gpu.AcceleratorIndex;
+		var stream = AcceleratorStreamPool.Rent(acceleratorIndex);
+		var kernel = gpu.HeuristicCombinedTrialDivisionKernel;
+		var flagView1D = gpu.HeuristicFlag!.View;
 
-		bool compositeDetected = false;
+		bool compositeDetected;
 		int compositeFlag = 0;
 
-		int groupALength = HeuristicPrimeSieves.GroupADivisors.Length;
-
 		flagView1D.CopyFromCPU(stream, ref compositeFlag, 1);
-		kernel.Launch(
-				stream!,
+
+		//         Index1D index,
+        // ArrayView<int> resultFlag,
+        // ulong n,
+        // ulong maxDivisorSquare,
+        // HeuristicGpuDivisorTableKind tableKind,
+        // HeuristicGpuDivisorTables tables)
+
+		var kernelLauncher = kernel.CreateLauncherDelegate<Action<AcceleratorStream, Index1D, byte, ArrayView<int>, ulong, ulong, HeuristicGpuDivisorTableKind, HeuristicGpuCombinedDivisorTables>>();
+		kernelLauncher(
+				stream,
 				1,
-				groupALength,
-				flagView,
+				nMod10,
+				flagView1D,
 				n,
 				maxDivisorSquare,
 				HeuristicGpuDivisorTableKind.GroupA,
-				gpu.HeuristicGpuTables);
+				gpu.DivisorTables);
 
 		flagView1D.CopyToCPU(stream, ref compositeFlag, 1);
 		stream!.Synchronize();
 
 		compositeDetected = compositeFlag != 0;
+		// compositeDetected = compositeFlag != 0;
 
-		if (!compositeDetected)
-		{
-			ReadOnlySpan<byte> endingOrder = GetGroupBEndingOrder(nMod10);
-			for (int i = 0; i < endingOrder.Length && !compositeDetected; i++)
-			{
-				byte ending = endingOrder[i];
-				HeuristicGpuDivisorTableKind tableKind = ending switch
-				{
-					1 => HeuristicGpuDivisorTableKind.GroupBEnding1,
-					7 => HeuristicGpuDivisorTableKind.GroupBEnding7,
-					9 => HeuristicGpuDivisorTableKind.GroupBEnding9,
-					_ => HeuristicGpuDivisorTableKind.GroupA,
-				};
+		// if (!compositeDetected)
+		// {
+		// 	ReadOnlySpan<byte> endingOrder = GetGroupBEndingOrder(nMod10);
+		// 	for (int i = 0; i < endingOrder.Length && !compositeDetected; i++)
+		// 	{
+		// 		byte ending = endingOrder[i];
+		// 		HeuristicGpuDivisorTableKind tableKind = ending switch
+		// 		{
+		// 			1 => HeuristicGpuDivisorTableKind.GroupBEnding1,
+		// 			7 => HeuristicGpuDivisorTableKind.GroupBEnding7,
+		// 			9 => HeuristicGpuDivisorTableKind.GroupBEnding9,
+		// 			_ => HeuristicGpuDivisorTableKind.GroupA,
+		// 		};
 
-				if (tableKind == HeuristicGpuDivisorTableKind.GroupA)
-				{
-					continue;
-				}
+		// 		if (tableKind == HeuristicGpuDivisorTableKind.GroupA)
+		// 		{
+		// 			continue;
+		// 		}
 
-				int divisorLength = GetGroupBDivisors(ending).Length;
+		// 		int divisorLength = GetGroupBDivisors(ending).Length;
 
-				compositeFlag = 0;
-				flagView1D.CopyFromCPU(stream, ref compositeFlag, 1);
-				kernel.Launch(
-					stream,
-						1,
-						divisorLength,
-						flagView,
-						n,
-						maxDivisorSquare,
-						tableKind,
-						gpu.HeuristicGpuTables);
-				flagView1D.CopyToCPU(stream, ref compositeFlag, 1);
-				stream.Synchronize();
-				compositeDetected = compositeFlag != 0;
-			}
-		}
+		// 		compositeFlag = 0;
+		// 		flagView1D.CopyFromCPU(stream, ref compositeFlag, 1);
+		// 		kernelLauncher(
+		// 			stream,
+		// 				1,
+		// 				flagView1D,
+		// 				n,
+		// 				maxDivisorSquare,
+		// 				tableKind,
+		// 				gpu.HeuristicGpuTables);
+		// 		flagView1D.CopyToCPU(stream, ref compositeFlag, 1);
+		// 		stream.Synchronize();
+		// 		compositeDetected = compositeFlag != 0;
+		// 	}
+		// }
 
-		gpu.Dispose();
+		AcceleratorStreamPool.Return(acceleratorIndex, stream);
+		gpu.Return();
 		// GpuPrimeWorkLimiter.Release();
 		return compositeDetected;
 	}
@@ -457,6 +466,7 @@ public sealed class HeuristicPrimeTester
 
 	[MethodImpl(MethodImplOptions.AggressiveInlining)]
 	internal static ulong ResolveHeuristicCycleLength(
+		HeuristicCombinedPrimeTesterAccelerator gpu,
 		ulong exponent,
 		in HeuristicDivisorPreparation preparation,
 		out bool cycleFromHint,
@@ -475,6 +485,7 @@ public sealed class HeuristicPrimeTester
 		MontgomeryDivisorData divisorData = preparation.DivisorData;
 
 		bool trySuccess = MersenneDivisorCycles.TryCalculateCycleLengthForExponentCpu(
+			gpu,
 			divisor,
 			exponent,
 			divisorData,

PerfectNumbers.Core/IMersenneNumberDivisorByDivisorTester.cs

@@ -20,6 +20,6 @@ public interface IMersenneNumberDivisorByDivisorTester
     {
         void CheckDivisor(ulong divisor, in MontgomeryDivisorData divisorData, ulong divisorCycle, in ReadOnlySpan<ulong> primes, Span<byte> hits);
 
-        void Dispose();
+        void Return();
     }
 }

PerfectNumbers.Core/MersenneDivisorCycles.cs

@@ -52,7 +52,7 @@ public class MersenneDivisorCycles
 		return _smallCycles!;
 	}
 
-	public static bool CycleEqualsExponent(ulong divisor, in MontgomeryDivisorData divisorData, ulong exponent)
+	public static bool CycleEqualsExponent(HeuristicCombinedPrimeTesterAccelerator gpu, ulong divisor, in MontgomeryDivisorData divisorData, ulong exponent)
 	{
 		if (CycleEqualsExponentForMersenneCandidate(divisor, divisorData, exponent))
 		{
@@ -82,7 +82,7 @@ public class MersenneDivisorCycles
 			return heuristicCycle == exponent;
 		}
 
-		if (TryCalculateCycleLengthForExponentCpu(divisor, exponent, divisorData, out ulong cycleLength, out bool _) && cycleLength != 0UL)
+		if (TryCalculateCycleLengthForExponentCpu(gpu, divisor, exponent, divisorData, out ulong cycleLength, out bool _) && cycleLength != 0UL)
 		{
 			return cycleLength == exponent;
 		}
@@ -260,6 +260,7 @@ public class MersenneDivisorCycles
 	}
 
 	public static bool TryCalculateCycleLengthForExponentCpu(
+		HeuristicCombinedPrimeTesterAccelerator gpu,
 		ulong divisor,
 		ulong exponent,
 		in MontgomeryDivisorData divisorData,
@@ -328,8 +329,8 @@ public class MersenneDivisorCycles
 			factorCounts[2UL] = twoCount;
 		}
 
-		bool exponentAccumulated = AccumulateFactors(exponent, factorCounts);
-		bool factorsAccumulated = exponentAccumulated && AccumulateFactors(k, factorCounts);
+		bool exponentAccumulated = AccumulateFactors(gpu, exponent, factorCounts);
+		bool factorsAccumulated = exponentAccumulated && AccumulateFactors(gpu, k, factorCounts);
 
 		if (factorsAccumulated)
 		{
@@ -344,6 +345,7 @@ public class MersenneDivisorCycles
 	}
 
 	private static bool AccumulateFactors(
+		HeuristicCombinedPrimeTesterAccelerator gpu,
 		ulong value,
 		Dictionary<ulong, int> counts)
 	{
@@ -353,7 +355,7 @@ public class MersenneDivisorCycles
 		}
 
 		Dictionary<ulong, int> scratch = ThreadStaticPools.RentFactorScratchDictionary();
-		bool success = TryFactorIntoCountsInternal(value, scratch);
+		bool success = TryFactorIntoCountsInternal(gpu, value, scratch);
 		if (!success)
 		{
 			scratch.Clear();
@@ -375,7 +377,7 @@ public class MersenneDivisorCycles
 	// private static ulong _tryFactorIntoCountsInternalHits;
 	// private static ulong _tryCalculateCycleLengthHeuristicHits;
 
-	private static bool TryFactorIntoCountsInternal(ulong value, Dictionary<ulong, int> counts)
+	private static bool TryFactorIntoCountsInternal(HeuristicCombinedPrimeTesterAccelerator gpu, ulong value, Dictionary<ulong, int> counts)
 	{
 		// The EvenPerfectBitScanner only requests factors for values >= 2 here. Leave the guard documented without executing it.
 		// if (value <= 1UL)
@@ -412,7 +414,7 @@ public class MersenneDivisorCycles
 		// Console.WriteLine($"MersenneDivisorCycles.TryFactorIntoCountsInternal hits {Volatile.Read(ref _tryFactorIntoCountsInternalHits)}");
 
 		// HeuristicPrimeTester primeTester = _primeTester ??= new();
-		if (PrimeTester.IsPrimeGpu(remaining))
+		if (HeuristicCombinedPrimeTester.IsPrimeGpu(gpu, remaining))
 		// if (PrimeTester.IsPrimeCpu(remaining, CancellationToken.None))
 		{
 			AddFactor(counts, remaining);
@@ -437,13 +439,13 @@ public class MersenneDivisorCycles
 		//     return false;
 		// }
 
-		if (!TryFactorIntoCountsInternal(factor, counts))
+		if (!TryFactorIntoCountsInternal(gpu, factor, counts))
 		{
 			return false;
 		}
 
 		// Guard the recursive calls to terminate once Pollard-Rho reduces either branch to 1.
-		if (quotient > 1UL && !TryFactorIntoCountsInternal(quotient, counts))
+		if (quotient > 1UL && !TryFactorIntoCountsInternal(gpu, quotient, counts))
 		{
 			return false;
 		}
@@ -958,7 +960,7 @@ public class MersenneDivisorCycles
 		// HeuristicPrimeTester primeTester = _primeTester ??= new();
 		// if (!skipPrimeOrderHeuristic && HeuristicPrimeTester.Exclusive.IsPrimeCpu(divisor, CancellationToken.None))
 		// if (!skipPrimeOrderHeuristic && primeTester.IsPrimeGpu(divisor))
-		if (!skipPrimeOrderHeuristic && PrimeTester.IsPrimeGpu(divisor))
+		if (!skipPrimeOrderHeuristic && HeuristicCombinedPrimeTester.IsPrimeGpu(divisor))
 		{
 			ulong computedOrder = PrimeOrderCalculator.Calculate(
 					divisor,

PerfectNumbers.Core/PerfectNumberConstants.cs

@@ -21,3 +21,4 @@ public static class PerfectNumberConstants
     // TODO: Promote these magic numbers into a runtime profile derived from EvenPerfectBitScanner.Benchmarks so we can retune
     // them automatically when the optimal ranges for 2kp+1 >= 138M change.
 }
+	

PerfectNumbers.Core/PrimeOrderCalculator.Cpu.cs

@@ -3,6 +3,7 @@ using System.Diagnostics;
 using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
+using ILGPU;
 using PerfectNumbers.Core.Cpu;
 using PerfectNumbers.Core.Gpu;
 using PerfectNumbers.Core.Gpu.Accelerators;
@@ -54,34 +55,39 @@ internal static partial class PrimeOrderCalculator
 		ulong phi = prime - 1UL;
 
 		PrimeOrderCalculatorAccelerator gpu = PrimeOrderCalculatorAccelerator.Rent(1);
+		HeuristicCombinedPrimeTesterAccelerator gpu2 = HeuristicCombinedPrimeTesterAccelerator.Rent(1);
 		if (IsGpuHeuristicDevice && PrimeOrderGpuHeuristics.TryCalculateOrder(prime, previousOrder, config, divisorData, out ulong gpuOrder))
 		{
 			PrimeOrderCalculatorAccelerator.Return(gpu);
+			HeuristicCombinedPrimeTesterAccelerator.Return(gpu2);
 			return gpuOrder;
 		}
 
-		PartialFactorResult phiFactors = PartialFactor(gpu, phi, config);
+		PartialFactorResult phiFactors = PartialFactor(gpu, gpu2, phi, config);
 
 		ulong result;
 		if (phiFactors.Factors is null)
 		{
 			result = prime <= PerfectNumberConstants.MaxQForDivisorCycles
-				? CalculateByFactorizationGpu(gpu, prime, divisorData)
-				: CalculateByFactorizationCpu(gpu, prime, divisorData);
+				? CalculateByFactorizationGpu(gpu, gpu2, prime, divisorData)
+				: CalculateByFactorizationCpu(gpu, gpu2, prime, divisorData);
 				
 			phiFactors.Dispose();
 			PrimeOrderCalculatorAccelerator.Return(gpu);
+			HeuristicCombinedPrimeTesterAccelerator.Return(gpu2);
 			return result;
 		}
 
-		result = RunHeuristicPipelineCpu(gpu, prime, previousOrder, config, divisorData, phi, phiFactors);
+		result = RunHeuristicPipelineCpu(gpu, gpu2, prime, previousOrder, config, divisorData, phi, phiFactors);
 		phiFactors.Dispose();
 		PrimeOrderCalculatorAccelerator.Return(gpu);
+		HeuristicCombinedPrimeTesterAccelerator.Return(gpu2);
 		return result;
 	}
 
 	private static ulong RunHeuristicPipelineCpu(
 		PrimeOrderCalculatorAccelerator gpu,
+		HeuristicCombinedPrimeTesterAccelerator gpu2,
 		ulong prime,
 		ulong? previousOrder,
 		in PrimeOrderSearchConfig config,
@@ -98,7 +104,7 @@ internal static partial class PrimeOrderCalculator
 		ulong candidateOrder = InitializeStartingOrderCpu(gpu, prime, phi, divisorData);
 		candidateOrder = ExponentLoweringCpu(candidateOrder, prime, phiFactors, divisorData);
 
-		if (TryConfirmOrderCpu(gpu, prime, candidateOrder, divisorData, config, out PartialFactorResult? orderFactors))
+		if (TryConfirmOrderCpu(gpu, gpu2, prime, candidateOrder, divisorData, config, out PartialFactorResult? orderFactors))
 		{
 			// GpuPrimeWorkLimiter.Release();
 			return candidateOrder;
@@ -108,10 +114,10 @@ internal static partial class PrimeOrderCalculator
 		{
 			orderFactors?.Dispose();
 			// GpuPrimeWorkLimiter.Release();
-			return CalculateByFactorizationGpu(gpu, prime, divisorData);
+			return CalculateByFactorizationGpu(gpu, gpu2, prime, divisorData);
 		}
 
-		if (TryHeuristicFinishCpu(gpu, prime, candidateOrder, previousOrder, divisorData, config, phiFactors, orderFactors, out ulong order))
+		if (TryHeuristicFinishCpu(gpu, gpu2, prime, candidateOrder, previousOrder, divisorData, config, phiFactors, orderFactors, out ulong order))
 		{
 			// GpuPrimeWorkLimiter.Release();
 			return order;
@@ -340,6 +346,7 @@ internal static partial class PrimeOrderCalculator
 
 	private static bool TryConfirmOrderCpu(
 		PrimeOrderCalculatorAccelerator gpu,
+		HeuristicCombinedPrimeTesterAccelerator gpu2,
 		ulong prime,
 		ulong order,
 		in MontgomeryDivisorData divisorData,
@@ -358,7 +365,7 @@ internal static partial class PrimeOrderCalculator
 			return false;
 		}
 
-		PartialFactorResult factorization = PartialFactor(gpu, order, config);
+		PartialFactorResult factorization = PartialFactor(gpu, gpu2, order, config);
 		if (factorization.Factors is null)
 		{
 			factorization.Dispose();
@@ -503,6 +510,7 @@ internal static partial class PrimeOrderCalculator
 
 	private static bool TryHeuristicFinishCpu(
 		PrimeOrderCalculatorAccelerator gpu,
+		HeuristicCombinedPrimeTesterAccelerator gpu2,
 		ulong prime,
 		ulong order,
 		ulong? previousOrder,
@@ -520,7 +528,7 @@ internal static partial class PrimeOrderCalculator
 		}
 
 		// Reuse the partial factorization from TryConfirmOrderCpu when available.
-		PartialFactorResult orderFactors = cachedOrderFactors ?? PartialFactor(gpu, order, config);
+		PartialFactorResult orderFactors = cachedOrderFactors ?? PartialFactor(gpu, gpu2, order, config);
 		try
 		{
 			if (orderFactors.Factors is null)
@@ -636,7 +644,7 @@ internal static partial class PrimeOrderCalculator
 
 					bool equalsOne = powStepper.InitializeCpuIsUnity(candidate);
 					powStepperInitialized = true;
-					if (equalsOne && TryConfirmCandidateCpu(gpu, prime, candidate, divisorData, config, ref powUsed, powBudget))
+					if (equalsOne && TryConfirmCandidateCpu(gpu, gpu2, prime, candidate, divisorData, config, ref powUsed, powBudget))
 					{
 						if (gpuPool is not null)
 						{
@@ -673,7 +681,7 @@ internal static partial class PrimeOrderCalculator
 						continue;
 					}
 
-					if (!TryConfirmCandidateCpu(gpu, prime, candidate, divisorData, config, ref powUsed, powBudget))
+					if (!TryConfirmCandidateCpu(gpu, gpu2, prime, candidate, divisorData, config, ref powUsed, powBudget))
 					{
 						continue;
 					}
@@ -884,9 +892,9 @@ internal static partial class PrimeOrderCalculator
 		}
 	}
 
-	private static bool TryConfirmCandidateCpu(PrimeOrderCalculatorAccelerator gpu, ulong prime, ulong candidate, in MontgomeryDivisorData divisorData, in PrimeOrderSearchConfig config, ref int powUsed, int powBudget)
+	private static bool TryConfirmCandidateCpu(PrimeOrderCalculatorAccelerator gpu, HeuristicCombinedPrimeTesterAccelerator gpu2, ulong prime, ulong candidate, in MontgomeryDivisorData divisorData, in PrimeOrderSearchConfig config, ref int powUsed, int powBudget)
 	{
-		PartialFactorResult factorization = PartialFactor(gpu, candidate, config);
+		PartialFactorResult factorization = PartialFactor(gpu, gpu2, candidate, config);
 		try
 		{
 			if (factorization.Factors is null)
@@ -1082,7 +1090,9 @@ internal static partial class PrimeOrderCalculator
 	// private static ulong _partialFactorPendingHits;
 	// private static ulong _partialFactorCofactorHits;
 
-	private static PartialFactorResult PartialFactor(PrimeOrderCalculatorAccelerator gpu, ulong value, in PrimeOrderSearchConfig config)
+	private static bool _goToGpu = true;
+
+	private static PartialFactorResult PartialFactor(PrimeOrderCalculatorAccelerator gpu, HeuristicCombinedPrimeTesterAccelerator gpu2, ulong value, in PrimeOrderSearchConfig config)
 	{
 		if (value <= 1UL)
 		{
@@ -1169,7 +1179,11 @@ internal static partial class PrimeOrderCalculator
 					// Console.WriteLine($"Partial factor hits {Volatile.Read(ref _partialFactorHits)}");
 
 					// bool isPrime = PrimeTester.IsPrimeCpu(composite, CancellationToken.None);
-					bool isPrime = PrimeTester.IsPrimeGpu(gpu, composite);
+					bool goToGpu = Volatile.Read(ref _goToGpu);
+					Volatile.Write(ref _goToGpu, !goToGpu);					
+					bool isPrime = goToGpu
+						? HeuristicCombinedPrimeTester.IsPrimeGpu(gpu2, composite)
+						: PrimeTester.IsPrime(composite);
 					// bool isPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(composite);
 
 					if (isPrime)
@@ -1241,7 +1255,7 @@ internal static partial class PrimeOrderCalculator
 				// Console.WriteLine($"Partial factor pending hits {Volatile.Read(ref _partialFactorPendingHits)}");
 
 				// bool isPrime = PrimeTester.IsPrimeCpu(composite, CancellationToken.None);
-				bool isPrime = PrimeTester.IsPrimeGpu(gpu, composite);
+				bool isPrime = HeuristicCombinedPrimeTester.IsPrimeGpu(gpu2, composite);
 				// bool isPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(composite);
 
 				entry = entry.WithPrimality(isPrime);
@@ -1278,7 +1292,8 @@ internal static partial class PrimeOrderCalculator
 			// Atomic.Add(ref _partialFactorCofactorHits, 1UL);
 			// Console.WriteLine($"Partial factor cofactor hits {Volatile.Read(ref _partialFactorCofactorHits)}");
 
-			cofactorIsPrime = PrimeTester.IsPrimeGpu(gpu, cofactor);
+			cofactorIsPrime = HeuristicCombinedPrimeTester.IsPrimeGpu(gpu2, cofactor);
+			// cofactorIsPrime = PrimeTester.IsPrimeGpu(gpu, cofactor);
 			// cofactorIsPrime = PrimeTester.IsPrimeGpu(cofactor);
 			// cofactorIsPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(cofactor);
 		}
@@ -1698,11 +1713,11 @@ internal static partial class PrimeOrderCalculator
 		exponents = newExponentSpan;
 	}
 
-	private static ulong CalculateByFactorizationCpu(PrimeOrderCalculatorAccelerator gpu, ulong prime, in MontgomeryDivisorData divisorData)
+	private static ulong CalculateByFactorizationCpu(PrimeOrderCalculatorAccelerator gpu, HeuristicCombinedPrimeTesterAccelerator gpu2, ulong prime, in MontgomeryDivisorData divisorData)
 	{
 		ulong phi = prime - 1UL;
 		Dictionary<ulong, int> counts = new(capacity: 8);
-		FactorCompletelyCpu(phi, counts);
+		FactorCompletelyCpu(gpu2, phi, counts);
 		if (counts.Count == 0)
 		{
 			return phi;
@@ -1746,9 +1761,9 @@ internal static partial class PrimeOrderCalculator
 		return order;
 	}
 
-	private static void FactorCompletelyCpu(ulong value, Dictionary<ulong, int> counts)
+	private static void FactorCompletelyCpu(HeuristicCombinedPrimeTesterAccelerator gpu, ulong value, Dictionary<ulong, int> counts)
 	{
-		FactorCompletely(value, counts, knownComposite: false);
+		FactorCompletely(gpu, value, counts, knownComposite: false);
 	}
 
 	// private static ulong _factorCompletelyHits;
@@ -1756,7 +1771,7 @@ internal static partial class PrimeOrderCalculator
 	// [ThreadStatic]
 	// private static HeuristicPrimeTester? _tester;
 
-	private static void FactorCompletely(ulong value, Dictionary<ulong, int> counts, bool knownComposite)
+	private static void FactorCompletely(HeuristicCombinedPrimeTesterAccelerator gpu, ulong value, Dictionary<ulong, int> counts, bool knownComposite)
 	{
 		if (value <= 1UL)
 		{
@@ -1768,7 +1783,8 @@ internal static partial class PrimeOrderCalculator
 		// HeuristicPrimeTester tester = _tester ??= new();
 
 		// bool isPrime = primeTester.HeuristicIsPrimeGpu(value);
-		bool isPrime = PrimeTester.IsPrimeGpu(value);
+		bool isPrime = HeuristicCombinedPrimeTester.IsPrimeGpu(gpu, value);
+		// bool isPrime = PrimeTester.IsPrimeGpu(value);
 		// bool isPrime = PrimeTester.IsPrimeGpu(value);
 		// bool isPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(value);
 		if (!knownComposite && isPrime)
@@ -1784,7 +1800,7 @@ internal static partial class PrimeOrderCalculator
 		// Console.WriteLine($"Factor completely after PollardRho hits {Volatile.Read(ref _factorCompletelyPollardRhoHits)}");
 
 		// isPrime = primeTester.HeuristicIsPrimeGpu(factor);
-		isPrime = PrimeTester.IsPrimeGpu(factor);
+		isPrime = HeuristicCombinedPrimeTester.IsPrimeGpu(gpu, factor);
 		// isPrime = PrimeTester.IsPrimeGpu(factor);
 		// isPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(factor);
 		if (isPrime)
@@ -1801,13 +1817,13 @@ internal static partial class PrimeOrderCalculator
 
 			if (remaining > 1UL)
 			{
-				FactorCompletely(remaining, counts, knownComposite: false);
+				FactorCompletely(gpu, remaining, counts, knownComposite: false);
 			}
 
 			return;
 		}
 
-		FactorCompletely(factor, counts, knownComposite: true);
+		FactorCompletely(gpu, factor, counts, knownComposite: true);
 
 		if (quotient == factor)
 		{
@@ -1821,7 +1837,7 @@ internal static partial class PrimeOrderCalculator
 			// Atomic.Add(ref _partialFactorCofactorHits, 1UL);
 			// Console.WriteLine($"Partial factor cofactor hits {Volatile.Read(ref _partialFactorCofactorHits)}");
 
-			isPrime = PrimeTester.IsPrimeGpu(quotient);
+			isPrime = HeuristicCombinedPrimeTester.IsPrimeGpu(gpu, quotient);
 			// isPrime = PrimeTester.IsPrimeGpu(quotient);
 			// isPrime = Open.Numeric.Primes.Prime.Numbers.IsPrime(quotient);
 		}
@@ -1832,7 +1848,7 @@ internal static partial class PrimeOrderCalculator
 		}
 		else
 		{
-			FactorCompletely(quotient, counts, knownComposite: true);
+			FactorCompletely(gpu, quotient, counts, knownComposite: true);
 		}
 	}
 

PerfectNumbers.Core/PrimeOrderCalculator.Gpu.cs

@@ -12,13 +12,13 @@ internal static partial class PrimeOrderCalculator
 
 	private const int GpuSmallPrimeFactorSlots = 64;
 
-	private static ulong CalculateByFactorizationGpu(PrimeOrderCalculatorAccelerator gpu, ulong prime, in MontgomeryDivisorData divisorData)
+	private static ulong CalculateByFactorizationGpu(PrimeOrderCalculatorAccelerator gpu, HeuristicCombinedPrimeTesterAccelerator gpu2, ulong prime, in MontgomeryDivisorData divisorData)
 	{
 		ulong phi = prime - 1UL;
 		Dictionary<ulong, int> counts = gpu.Pow2ModEntriesToTestOnHost;
 		counts.Clear();
 		
-		FactorCompletelyCpu(phi, counts);
+		FactorCompletelyCpu(gpu2, phi, counts);
 		if (counts.Count == 0)
 		{
 			return phi;