X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Ftt.h;h=d2f1ce65c17053475bd1797404dc209972dd07db;hb=9742fb10fd83e82ad760e4cac5cef3d6dff670ed;hp=a983805b19afdc5ae207097c4a2539862d0a4740;hpb=dc3508d157118cbda500bb42595575105a4602e5;p=stockfish

diff --git a/src/tt.h b/src/tt.h
index a983805b..d2f1ce65 100644
--- a/src/tt.h
+++ b/src/tt.h
@@ -1,7 +1,7 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2016 Marco Costalba, Joona Kiiski, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -76,8 +76,9 @@ private:
 /// A TranspositionTable consists of a power of 2 number of clusters and each
 /// cluster consists of ClusterSize number of TTEntry. Each non-empty entry
 /// contains information of exactly one position. The size of a cluster should
-/// not be bigger than a cache line size. In case it is less, it should be padded
-/// to guarantee always aligned accesses.
+/// divide the size of a cache line size, to ensure that clusters never cross
+/// cache lines. This ensures best cache performance, as the cacheline is
+/// prefetched, as soon as possible.
 
 class TranspositionTable {
 
@@ -86,10 +87,10 @@ class TranspositionTable {
 
   struct Cluster {
     TTEntry entry[ClusterSize];
-    char padding[2]; // Align to the cache line size
+    char padding[2]; // Align to a divisor of the cache line size
   };
 
-  static_assert(sizeof(Cluster) == CacheLineSize / 2, "Cluster size incorrect");
+  static_assert(CacheLineSize % sizeof(Cluster) == 0, "Cluster size incorrect");
 
 public:
  ~TranspositionTable() { free(mem); }