diff --git a/StgSharp.Common/Mathematics/Linear/MatrixParallel.Execute.cs b/StgSharp.Common/Mathematics/Linear/MatrixParallel.Execute.cs
index 62da90e6..40d6caef 100644
--- a/StgSharp.Common/Mathematics/Linear/MatrixParallel.Execute.cs
+++ b/StgSharp.Common/Mathematics/Linear/MatrixParallel.Execute.cs
@@ -28,15 +28,8 @@
 //     
 // -----------------------------------------------------------------------
 // -----------------------------------------------------------------------
-using StgSharp.HighPerformance;
 using System;
-using System.Collections.Generic;
-using System.Formats.Asn1;
-using System.Linq;
-using System.Numerics;
 using System.Runtime.CompilerServices;
-using System.Text;
-using System.Threading.Tasks;
 
 namespace StgSharp.Mathematics
 {
@@ -98,7 +91,7 @@ namespace StgSharp.Mathematics
                 lLimit = pCount - p->LeftPrimOffset,
                 rLimit = pCount - p->RightPrimOffset,
                 aLimit = pCount - p->ResultPrimOffset;
-            delegate* unmanaged[Cdecl]<nint,nint,nint, ScalarPacket*, void> op =
+            delegate* unmanaged[Cdecl]<nint, nint, nint, ScalarPacket*, void> op =
                     (delegate* unmanaged[Cdecl]<nint, nint, nint, ScalarPacket*, void>)p->ComputeHandle;
             ScalarPacket* scalar = p->Scalar;
             for (long i = 0; i < pCount; i++)
diff --git a/StgSharp.Common/Mathematics/Linear/MatrixParallel.Publish.cs b/StgSharp.Common/Mathematics/Linear/MatrixParallel.Publish.cs
index 952bec45..2bc26ebf 100644
--- a/StgSharp.Common/Mathematics/Linear/MatrixParallel.Publish.cs
+++ b/StgSharp.Common/Mathematics/Linear/MatrixParallel.Publish.cs
@@ -76,10 +76,22 @@ namespace StgSharp.Mathematics
             package->ElementSize = sizeof(T);
             package->ComputeMode = 3;
 
-            int 
-                small_4 = c4 / length,
-                larget_4
+            if ((c3 | c4) > 0) { } else
+            {
+                int
+                    small_4_size = c4 / LargeWrapCount,
+                    large_4_size = small_4_size + 1,
+                    small_3_size = c3 / LargeWrapCount,
+                    large_3_size = small_3_size + 1;
+                int
+                    large_4_count = c4 % LargeWrapCount,
+                    small_4_count = LargeWrapCount - large_4_count,
+                    large_3_count = c3 % LargeWrapCount,
+                    small_3_count = LargeWrapCount - large_3_count;
+                for (int i = 0; i < large_4_count; i++) { }
 
+                // TODO maybe a task slice method is good?
+            }
         }
 
     }
diff --git a/StgSharp.Common/Mathematics/Linear/MatrixParallel.cs b/StgSharp.Common/Mathematics/Linear/MatrixParallel.cs
index a1721bf0..69ee58fa 100644
--- a/StgSharp.Common/Mathematics/Linear/MatrixParallel.cs
+++ b/StgSharp.Common/Mathematics/Linear/MatrixParallel.cs
@@ -28,22 +28,11 @@
 //     
 // -----------------------------------------------------------------------
 // -----------------------------------------------------------------------
-using StgSharp.HighPerformance;
-using StgSharp.HighPerformance.Memory;
-
 using System;
 using System.Collections.Generic;
-using System.ComponentModel;
 using System.Diagnostics.CodeAnalysis;
-using System.IO.Pipes;
-using System.Linq;
-using System.Reflection.Metadata;
 using System.Runtime.CompilerServices;
-using System.Runtime.ExceptionServices;
-using System.Text;
 using System.Threading;
-using System.Threading.Channels;
-using System.Threading.Tasks;
 
 namespace StgSharp.Mathematics
 {
@@ -68,7 +57,6 @@ namespace StgSharp.Mathematics
     {
 
         private static Thread[] _threads;
-        private static MatrixParallelWrap[] _wraps;
         private static readonly (int a, int b)[] LookupTable = [
             (1, 1),
             (0, 2),
@@ -87,9 +75,7 @@ namespace StgSharp.Mathematics
         ];
         private static bool _meaningful;
 
-        private static int LargeWrapCount;
         private static volatile int RemainThreadCount = 0;
-        private static int SmallWrapCount;
         private static readonly object _lock = new();
         private static ThreadPriority _AfterWork = ThreadPriority.Lowest;
 
@@ -139,25 +125,37 @@ namespace StgSharp.Mathematics
             _threads = new Thread[count];
             if (count < 6)
             {
-                count = count == 3 ? 3 : 4;
-                _wraps = [ new MatrixParallelWrap(0, count, true) ];
-                (LargeWrapCount, SmallWrapCount) = count == 3 ? (1,0) : (0,1);
+                if (count == 3)
+                {
+                    SmallWraps = [ new MatrixParallelWrap(0, count, true) ];
+                    LargeWraps = [];
+                    (LargeWrapCount, SmallWrapCount) = (1, 0);
+                } else
+                {
+                    count = 4;
+                    LargeWraps = [ new MatrixParallelWrap(0, count, true) ];
+                    SmallWraps = [];
+                    (LargeWrapCount, SmallWrapCount) = (0, 1);
+                }
             } else if (count == 6)
             {
-                _wraps = [
+                SmallWraps = [
                     new MatrixParallelWrap(0, 3, true),
                     new MatrixParallelWrap(3, 3, false)
                 ];
+                LargeWraps = [];
+                (LargeWrapCount, SmallWrapCount) = (0, 2);
             } else
             {
                 (int _3wrap, int _4wrap) = FastDecompose(count);
-                _wraps = new MatrixParallelWrap[_3wrap + _4wrap];
-                int id = 0, idx = 0;
-                for (; idx < _3wrap; idx++, id += 3) {
-                    _wraps[idx] = new MatrixParallelWrap(idx, 3, id == 0);
+                LargeWraps = new MatrixParallelWrap[ _4wrap];
+                SmallWraps = new MatrixParallelWrap[ _3wrap];
+                int id = 0;
+                for (int idx = 0; idx < _3wrap; idx++, id += 3) {
+                    SmallWraps[idx] = new MatrixParallelWrap(idx, 3, id == 0);
                 }
-                for (; idx < _3wrap + _4wrap; idx++, id += 4) {
-                    _wraps[idx] = new MatrixParallelWrap(id, 4, id == 0);
+                for (int idx = 0; idx < _3wrap + _4wrap; idx++, id += 4) {
+                    LargeWraps[idx] = new MatrixParallelWrap(id, 4, id == 0);
                 }
             }
             LeaderHandle = new MatrixParallelWrap.Handle(0, _wraps[0]);
@@ -344,6 +342,14 @@ namespace StgSharp.Mathematics
             #endregion
         }
 
+        #region wrap field
+
+        private static MatrixParallelWrap[] LargeWraps;
+        private static MatrixParallelWrap[] SmallWraps;
+        private static int LargeWrapCount;
+        private static int SmallWrapCount;
+
+    #endregion
     }
 
     public enum SleepMode