On Wed, 8 Nov 2023 11:55:22 GMT, Glavo <d...@openjdk.org> wrote: > This PR significantly speeds up decompressing resources in Jimage while > significantly reducing temporary memory allocations in the process. > > This will improve startup speed for runtime images generated using `jlink > --compress 1` and `jlink --compress 2` . > > I generated a runtime image containing javac using `jlink --compress 1 > --add-modules jdk.compiler` and tested the time it took to compile a simple > HelloWorld program 20 times using `perf stat -r20 javac > /dev/shm/HelloWorld.java`, this PR reduces the total time taken from 17830ms > to 13598ms (31.12% faster).
I had to merge with master to get jlink to work, perhaps some local issue since Classfile API has been moving around. While the improvement to `--compress 1` are impressive, this compression mode is effectively deprecated. I'm not sure your improvements to it here will be enough to reverse that decision (it's still a bit behind on all measures, no?). Perhaps it would be better to split out those changes and move forward with and focus this on the zip decompressor enhancements? ------------- PR Review: https://git.openjdk.org/jdk/pull/16556#pullrequestreview-1818606132
