From 49dfc50b1286019ab706c961ab609bed1828d76d Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Tue, 9 Mar 2010 15:46:20 +0100 Subject: [PATCH 1/1] Reduce increase progression of aspiration window Currently, in case of fail high/low we research with a window increased by 2*AspirationDelta at first attempt, this patch instead makes the research be done with an increase of just AspirationDelta size, in case of a consecutive fail we will widen to 2*AspirationDelta and so on. After Joona's test: Orig - Mod: 850 - 890 Signed-off-by: Marco Costalba --- src/search.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/search.cpp b/src/search.cpp index 1eddff58..02fc41be 100644 --- a/src/search.cpp +++ b/src/search.cpp @@ -931,8 +931,8 @@ namespace { print_pv_info(pos, ss, alpha, beta, value); // Prepare for a research after a fail high, each time with a wider window - researchCountFH++; *betaPtr = beta = Min(beta + AspirationDelta * (1 << researchCountFH), VALUE_INFINITE); + researchCountFH++; } // End of fail high loop @@ -1017,8 +1017,8 @@ namespace { break; // Prepare for a research after a fail low, each time with a wider window - researchCountFL++; *alphaPtr = alpha = Max(alpha - AspirationDelta * (1 << researchCountFL), -VALUE_INFINITE); + researchCountFL++; } // Fail low loop -- 2.39.2