folkertdev
commented
4 months ago as a data point, commit 80481805d6a0bfffb4b9e29bb4ec6a363ec6a41d
Benchmark 1 (29 runs): cargo run --release --example compress 1 ng silesia-small.tar
measurement mean ± σ min … max outliers delta
wall_time 175ms ± 8.58ms 168ms … 217ms 1 ( 3%) 0%
peak_rss 26.8MB ± 87.3KB 26.6MB … 27.0MB 0 ( 0%) 0%
cpu_cycles 515M ± 6.88M 505M … 529M 0 ( 0%) 0%
instructions 744M ± 35.3K 744M … 744M 1 ( 3%) 0%
cache_references 11.3M ± 1.18M 9.08M … 14.1M 0 ( 0%) 0%
cache_misses 2.25M ± 66.4K 2.12M … 2.40M 1 ( 3%) 0%
branch_misses 4.13M ± 15.1K 4.10M … 4.17M 0 ( 0%) 0%
Benchmark 2 (27 runs): cargo run --release --example compress 1 rs silesia-small.tar
measurement mean ± σ min … max outliers delta
wall_time 191ms ± 4.14ms 187ms … 207ms 1 ( 4%) 💩+ 9.2% ± 2.1%
peak_rss 26.7MB ± 93.5KB 26.6MB … 26.9MB 0 ( 0%) - 0.3% ± 0.2%
cpu_cycles 580M ± 10.7M 570M … 619M 1 ( 4%) 💩+ 12.7% ± 0.9%
instructions 873M ± 31.4K 873M … 873M 0 ( 0%) 💩+ 17.3% ± 0.0%
cache_references 11.4M ± 1.16M 9.31M … 13.6M 0 ( 0%) + 0.9% ± 5.6%
cache_misses 2.33M ± 74.4K 2.22M … 2.49M 0 ( 0%) 💩+ 3.6% ± 1.7%
branch_misses 4.39M ± 42.1K 4.34M … 4.52M 1 ( 4%) 💩+ 6.2% ± 0.4%
we are consistently ~10% slower than zlib-ng on deflate. This fluctuates with the different compression levels, but currently none of then are on-par with zlib-ng.
There is so far no obvious reason for this slowdown, so it's likely a "death by a thousand papercuts" sort of thing.