| commit | 8b8f926fc3f0e8f002d0a8e97aab9500e4db83a7 | [log] [tgz] |
|---|---|---|
| author | Keith Randall <khr@golang.org> | Mon Jul 06 20:46:31 2020 -0700 |
| committer | Keith Randall <khr@golang.org> | Mon Aug 17 22:00:17 2020 +0000 |
| tree | d6b48dfe11fcc7a5ff93cf99fc625c79d5aec234 | |
| parent | 4e5ed83e8d2fbbbc8f6524f40ab3b6733dc57a38 [diff] |
runtime: bit parallel implementation of findBitRange64 Use a bit-parallel implementation of findBitRange64. It uses a repeated shift-'N-and technique to erase all the free marks that are too small for the allocation. Also some small improvements to find1. name old time/op new time/op delta FindBitRange64/Pattern00Size2-16 4.19ns ± 0% 2.26ns ± 0% -46.04% (p=0.000 n=10+8) FindBitRange64/Pattern00Size8-16 4.19ns ± 0% 2.12ns ± 0% -49.35% (p=0.000 n=9+10) FindBitRange64/Pattern00Size32-16 4.20ns ± 0% 2.12ns ± 0% -49.49% (p=0.000 n=10+8) FindBitRange64/PatternFFFFFFFFFFFFFFFFSize2-16 2.13ns ± 0% 2.27ns ± 0% +6.28% (p=0.000 n=10+10) FindBitRange64/PatternFFFFFFFFFFFFFFFFSize8-16 2.13ns ± 0% 4.46ns ± 0% +109.39% (p=0.000 n=10+9) FindBitRange64/PatternFFFFFFFFFFFFFFFFSize32-16 2.13ns ± 1% 5.58ns ± 0% +162.37% (p=0.000 n=10+9) FindBitRange64/PatternAASize2-16 22.2ns ± 0% 2.3ns ± 0% -89.82% (p=0.000 n=9+8) FindBitRange64/PatternAASize8-16 22.2ns ± 0% 2.1ns ± 1% -90.41% (p=0.000 n=9+10) FindBitRange64/PatternAASize32-16 22.2ns ± 0% 2.1ns ± 1% -90.43% (p=0.000 n=10+10) FindBitRange64/PatternAAAAAAAAAAAAAAAASize2-16 156ns ± 1% 2ns ± 0% -98.54% (p=0.000 n=10+10) FindBitRange64/PatternAAAAAAAAAAAAAAAASize8-16 155ns ± 1% 2ns ± 0% -98.63% (p=0.000 n=10+8) FindBitRange64/PatternAAAAAAAAAAAAAAAASize32-16 155ns ± 0% 2ns ± 1% -98.63% (p=0.000 n=8+10) FindBitRange64/Pattern80000000AAAAAAAASize2-16 81.2ns ± 0% 2.3ns ± 1% -97.21% (p=0.000 n=10+10) FindBitRange64/Pattern80000000AAAAAAAASize8-16 81.1ns ± 0% 2.1ns ± 0% -97.39% (p=0.000 n=10+9) FindBitRange64/Pattern80000000AAAAAAAASize32-16 81.1ns ± 0% 2.1ns ± 0% -97.38% (p=0.000 n=10+10) FindBitRange64/PatternAAAAAAAA00000001Size2-16 76.8ns ± 1% 2.3ns ± 0% -97.05% (p=0.000 n=10+10) FindBitRange64/PatternAAAAAAAA00000001Size8-16 76.6ns ± 0% 2.1ns ± 0% -97.23% (p=0.000 n=8+10) FindBitRange64/PatternAAAAAAAA00000001Size32-16 76.7ns ± 0% 2.1ns ± 0% -97.23% (p=0.000 n=9+9) FindBitRange64/PatternBBBBBBBBBBBBBBBBSize2-16 2.13ns ± 0% 2.27ns ± 0% +6.57% (p=0.000 n=8+8) FindBitRange64/PatternBBBBBBBBBBBBBBBBSize8-16 76.7ns ± 0% 2.9ns ± 0% -96.20% (p=0.000 n=9+10) FindBitRange64/PatternBBBBBBBBBBBBBBBBSize32-16 76.7ns ± 0% 2.9ns ± 0% -96.20% (p=0.000 n=10+10) FindBitRange64/Pattern80000000BBBBBBBBSize2-16 2.12ns ± 0% 2.27ns ± 1% +6.74% (p=0.000 n=10+10) FindBitRange64/Pattern80000000BBBBBBBBSize8-16 44.8ns ± 0% 2.9ns ± 0% -93.49% (p=0.000 n=9+10) FindBitRange64/Pattern80000000BBBBBBBBSize32-16 44.9ns ± 0% 2.9ns ± 0% -93.49% (p=0.000 n=10+8) FindBitRange64/PatternBBBBBBBB00000001Size2-16 4.20ns ± 1% 2.27ns ± 1% -46.02% (p=0.000 n=10+10) FindBitRange64/PatternBBBBBBBB00000001Size8-16 44.9ns ± 0% 2.9ns ± 1% -93.51% (p=0.000 n=10+9) FindBitRange64/PatternBBBBBBBB00000001Size32-16 44.9ns ± 0% 2.9ns ± 0% -93.51% (p=0.000 n=10+9) FindBitRange64/PatternCCCCCCCCCCCCCCCCSize2-16 4.19ns ± 0% 2.26ns ± 0% -46.10% (p=0.000 n=10+10) FindBitRange64/PatternCCCCCCCCCCCCCCCCSize8-16 76.5ns ± 0% 2.9ns ± 0% -96.19% (p=0.000 n=8+7) FindBitRange64/PatternCCCCCCCCCCCCCCCCSize32-16 76.5ns ± 0% 2.9ns ± 0% -96.19% (p=0.000 n=10+8) FindBitRange64/Pattern4444444444444444Size2-16 76.4ns ± 0% 2.3ns ± 0% -97.04% (p=0.000 n=8+10) FindBitRange64/Pattern4444444444444444Size8-16 76.5ns ± 0% 2.1ns ± 0% -97.23% (p=0.000 n=9+10) FindBitRange64/Pattern4444444444444444Size32-16 76.5ns ± 0% 2.1ns ± 0% -97.23% (p=0.000 n=8+10) FindBitRange64/Pattern4040404040404040Size2-16 40.3ns ± 0% 2.3ns ± 0% -94.38% (p=0.000 n=7+10) FindBitRange64/Pattern4040404040404040Size8-16 40.2ns ± 0% 2.1ns ± 0% -94.75% (p=0.000 n=10+10) FindBitRange64/Pattern4040404040404040Size32-16 40.2ns ± 0% 2.1ns ± 0% -94.76% (p=0.000 n=10+6) FindBitRange64/Pattern4000400040004000Size2-16 22.2ns ± 0% 2.2ns ± 0% -89.86% (p=0.001 n=8+9) FindBitRange64/Pattern4000400040004000Size8-16 22.2ns ± 0% 2.1ns ± 0% -90.52% (p=0.000 n=8+10) FindBitRange64/Pattern4000400040004000Size32-16 22.2ns ± 1% 2.1ns ± 0% -90.50% (p=0.000 n=10+10) The cases that slow down aren't really that slow, and those inputs never actually occur (there's a short circuit before the call to findBitRange64 for that case). Change-Id: I50fae62915098032d8ce7fa57ef29eee9deb01ba Reviewed-on: https://go-review.googlesource.com/c/go/+/241279 Reviewed-by: Michael Knyszek <mknyszek@google.com>
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