libdeflate is significantly faster than vanilla zlib, zlib-ng, and Cloudflare zlib. It is also MIT-licensed (so no licensing concerns). In addition, it simplifies a lot of the native code (something that's been tricky to get right).
While we're at it, I have also taken the time to fine-time compression in Velocity in general. Thanks to this work, native compression only requires one JNI call, an improvement from the more than 2 (sometimes up to 5) that were possible before. This optimization also extends to the existing Java compressors, though they require potentially two JNI calls.
zlib-ng boasts higher throughput than regular zlib, by combining patches
from Cloudflare, zlib, and ARM's improvements to zlib along with a more
modern codebase.
Profiling consistently shows that compression is the largest CPU expense
by far, so even a minor speed-up here is significant.
