On Wed, 25 Sep 2024 13:43:49 GMT, Claes Redestad <redes...@openjdk.org> wrote:
>> This PR suggests refactoring `ZipFile.Source.initCEN` to move as much logic >> as possible into the per-entry method processor. This inner method will be >> called often and JIT optimized earlier in the bootstrap sequence. >> >> Startup tests using the OpenJDK benchmarks.jar show a ~1ms improvement on >> both my M1 macbook and my x64 wokstation, while we also improve on relevant >> throughput microbenchmarks: >> >> >> Name (size) Cnt Base Error Test Error >> Unit Change >> openCloseZipFile 512 15 61372.449 ± 1197.432 58081.423 ± 1751.988 >> ns/op 1.06x (p = 0.000*) >> openCloseZipFile 1024 15 117953.727 ± 3202.274 112548.875 ± 5126.665 >> ns/op 1.05x (p = 0.001*) >> openCloseZipFilex2 512 15 62141.795 ± 674.121 60520.017 ± 2438.346 >> ns/op 1.03x (p = 0.017 ) >> openCloseZipFilex2 1024 15 117959.071 ± 1528.426 111773.937 ± 1604.412 >> ns/op 1.06x (p = 0.000*) >> * = significant > > Claes Redestad has updated the pull request incrementally with one additional > commit since the last revision: > > Typo There is a lot going on in this PR.. I've been playing with similar, but different ideas lately and I'm wondering if we could get away with less intrusive changes and still boost performance. Instead of pushing everything into `processNextCENEntry`, how about we instead extract methods for checking the fixed-length CEN header and for checking the variable-length CEN header fields (headerSize, extra and comment)? Here's a sketch of what I'm thinking: https://github.com/openjdk/jdk/compare/master...eirbjo:initCEN-extract-validation?expand=0 This PR: Benchmark (size) Mode Cnt Score Error Units ZipFileOpen.openCloseZipFile 512 avgt 15 104987.960 ? 4191.855 ns/op ZipFileOpen.openCloseZipFile 1024 avgt 15 172605.991 ? 3546.599 ns/op ZipFileOpen.openCloseZipFilex2 512 avgt 15 113737.426 ? 5797.246 ns/op ZipFileOpen.openCloseZipFilex2 1024 avgt 15 189276.928 ? 3195.026 ns/op My branch Benchmark (size) Mode Cnt Score Error Units ZipFileOpen.openCloseZipFile 512 avgt 15 100435.644 ? 2862.724 ns/op ZipFileOpen.openCloseZipFile 1024 avgt 15 165181.306 ? 2445.885 ns/op ZipFileOpen.openCloseZipFilex2 512 avgt 15 103644.570 ? 1615.982 ns/op ZipFileOpen.openCloseZipFilex2 1024 avgt 15 170362.938 ? 3421.632 ns/op ------------- PR Comment: https://git.openjdk.org/jdk/pull/21133#issuecomment-2374942705
