Maximum aspiration delta of 24

After 9080 games
1430 - 1342 - 6308  ELO +3 (+- 2.9)

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/search.cpp b/src/search.cpp
index 5196e86277880817d623b6c94645874d0ebe744e..fba9e53559f5b883f0cd479923ac2abe7a88ab78 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -657,7 +657,7 @@ namespace {
             int prevDelta1 = bestValues[iteration - 1] - bestValues[iteration - 2];
             int prevDelta2 = bestValues[iteration - 2] - bestValues[iteration - 3];
 
-            aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 64);
+            aspirationDelta = Min(Max(abs(prevDelta1) + abs(prevDelta2) / 2, 16), 24);
             aspirationDelta = (aspirationDelta + 7) / 8 * 8; // Round to match grainSize
 
             alpha = Max(bestValues[iteration - 1] - aspirationDelta, -VALUE_INFINITE);