From d09f34cc555e60dbd57ab7c9f268daf895922225 Mon Sep 17 00:00:00 2001 From: Dave Cheney Date: Sun, 28 Apr 2013 00:18:11 +1000 Subject: [PATCH] runtime: tune appendCrossover for arm Turns out the optimal value is 8 on cortex-A9 systems (pandaboard) benchmark old ns/op new ns/op delta BenchmarkAppend 907 908 +0.11% BenchmarkAppend1Byte 101 101 +0.00% BenchmarkAppend4Bytes 116 116 +0.00% BenchmarkAppend8Bytes 139 138 -0.72% BenchmarkAppend16Bytes 185 158 -14.59% BenchmarkAppend32Bytes 131 131 +0.00% BenchmarkAppendStr1Byte 72 72 +0.00% BenchmarkAppendStr4Bytes 93 93 -0.21% BenchmarkAppendStr8Bytes 116 116 +0.00% BenchmarkAppendStr16Bytes 161 125 -22.36% BenchmarkAppendStr32Bytes 102 102 +0.00% BenchmarkAppendSpecialCase 613 613 +0.00% R=golang-dev, r CC=golang-dev https://golang.org/cl/8863045 --- src/pkg/runtime/arch_arm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/pkg/runtime/arch_arm.h b/src/pkg/runtime/arch_arm.h index bb65d3faf10..27c70c10527 100644 --- a/src/pkg/runtime/arch_arm.h +++ b/src/pkg/runtime/arch_arm.h @@ -6,5 +6,5 @@ enum { thechar = '5', BigEndian = 0, CacheLineSize = 32, - appendCrossover = 16 + appendCrossover = 8 };