Add defensive try/catch around setting processor affinity (for AMD sy…

…stems which threw an Exception). Add dump-processor command to UCI.
dje-dev · Jan 3, 2021 · 2f09a83 · 2f09a83
1 parent 19cebb0
commit 2f09a83
Show file tree

Hide file tree

Showing 2 changed files with 45 additions and 17 deletions.
diff --git a/src/Ceres.Base/OperatingSystem/HardwareManager.cs b/src/Ceres.Base/OperatingSystem/HardwareManager.cs
@@ -68,29 +68,52 @@ public static void VerifyHardwareSoftwareCompatability()
 
     static bool haveAffinitizedSingle = false;
 
+
+    /// <summary>
+    /// Write diagnostic information to console relating to processor configuration.
+    /// </summary>
+    public static void DumpProcessorInfo()
+    {
+      Console.WriteLine("NumCPUSockets: " + WindowsHardware.NumCPUSockets);
+      Console.WriteLine("NumProcessors: " + System.Environment.ProcessorCount);
+      Console.WriteLine("Affinity Mask: " + Process.GetCurrentProcess().ProcessorAffinity);
+    }
+
     private static void AffinitizeSingleProcessor()
     {
-      // NOTE: Someday it would be desirable to allow different
-      //       logical calculations (e.g. chess tree searches)
-      //       to be placed on distinct sockets, and not restrict
-      //       all computation to a single socket.
-      //       But then we'd have to abandon use of TPL and .NET thread pool
-      //       completely and use our own versions which were processor constrained.
-      bool isMultisocket = WindowsHardware.NumCPUSockets > 1;
-      if (isMultisocket)
+      try
       {
-        // This dramatically improves performance (multithreading)
-        Process Proc = Process.GetCurrentProcess();
-        long AffinityMask = (long)Proc.ProcessorAffinity;
-        // TODO: need to calculate correct mask. Currently below we only take half the bits (processors)
-        var mask = (1 << (System.Environment.ProcessorCount / 2)) - 1;
-        AffinityMask &= mask; 
-        Proc.ProcessorAffinity = (IntPtr)AffinityMask;
-
-        haveAffinitizedSingle = true;
+        // NOTE: Someday it would be desirable to allow different
+        //       logical calculations (e.g. chess tree searches)
+        //       to be placed on distinct sockets, and not restrict
+        //       all computation to a single socket.
+        //       But then we'd have to abandon use of TPL and .NET thread pool
+        //       completely and use our own versions which were processor constrained.
+        bool isMultisocket = WindowsHardware.NumCPUSockets > 1;
+        if (isMultisocket)
+        {
+          // This dramatically improves performance (multithreading)
+          Process Proc = Process.GetCurrentProcess();
+          long AffinityMask = (long)Proc.ProcessorAffinity;
+          // TODO: need to calculate correct mask. Currently below we only take half the bits (processors)
+          var mask = (1 << (System.Environment.ProcessorCount / 2)) - 1;
+          AffinityMask &= mask;
+          Proc.ProcessorAffinity = (IntPtr)AffinityMask;
+
+          haveAffinitizedSingle = true;
+        }
       }
+      catch (Exception exc)
+      {
+        // Some AMD systems fail when setting affinity mask
+        // Therefore recover gracefully
+        // TODO: resolve this on AMD systems
+        Console.WriteLine("Note: failure in call to AffinitizeSingleProcessor.");
+      }
+
     }
 
+
   }
 }
 
diff --git a/src/Ceres.Features/UCI/UCIManager.cs b/src/Ceres.Features/UCI/UCIManager.cs
@@ -35,6 +35,7 @@
 using System.Collections.Generic;
 using Ceres.MCTS.Params;
 using Ceres.MCTS.MTCSNodes.Storage;
+using Ceres.Base.OperatingSystem;
 
 #endregion
 
@@ -259,6 +260,10 @@ public void PlayUCI()
               Console.WriteLine("info string No search manager created");
             break;
 
+          case "dump-processor":
+            HardwareManager.DumpProcessorInfo();
+            break;
+
           case "dump-time":
             if (curManager != null)
               curManager.DumpTimeInfo();