http://hackcasual.io/lzhamtestmin.html
That's timing on decompressing 4MB of floats from a 1.19MB input file On Friday, September 18, 2015 at 11:02:22 AM UTC-7, Charles Vaughn wrote: > > I'll try to post a demo today. There's an interesting aspect to LZHAM's > decoder, it's implemented with coroutines. My changes disable those, as > they cause degenerate performance in a lot of cases, by creating massive > switch statements. > > If at least some of the coroutine yield points could be made to work > without code bloat or speed impact, it would allow for streaming > decompression which would go along way to reducing the overall impact of > running the decompressor in Javascript. > > On Friday, September 18, 2015 at 10:44:00 AM UTC-7, Charles Vaughn wrote: >> >> I've got a little benchmark uncompressing 4MB of floats. On Chrome it's >> 80ms, so 50MBps. >> >> On Wednesday, September 16, 2015 at 2:37:15 PM UTC-7, Alon Zakai wrote: >>> >>> I'm curious what decompression speeds you see for lzham? The compression >>> ratios are impressive, but I assume that's at the cost of taking longer to >>> unpack. >>> >>> On Tue, Sep 15, 2015 at 7:17 PM, Charles Vaughn <cva...@gmail.com> >>> wrote: >>> >>>> If you're interested in checking out LZHAM, I've got that building for >>>> emscripten here: https://github.com/hackcasual/lzham_codec >>>> >>>> For bananabread, I saw the following results for of the models: >>>> >>>> rw-rw-r-- 1 charles charles 385692 Sep 15 19:12 m134_hudguns.blend >>>> -rw-rw-r-- 1 charles charles 138954 Sep 15 19:13 >>>> m134_hudguns.blend.lz4 >>>> -rw-rw-r-- 1 charles charles 83108 Sep 15 19:14 >>>> m134_hudguns.blend.lzham >>>> >>>> On Tuesday, September 8, 2015 at 5:11:26 PM UTC-7, Alon Zakai wrote: >>>>> >>>>> incoming now has optional LZ4 compression for file packages. What this >>>>> lets you do is pre-compress your filesystem data, and keep it compressed >>>>> in >>>>> memory, and only decompress chunks on demand as they are read. This means >>>>> that you can reduce the total amount of memory used by your application. >>>>> >>>>> LZ4 ( https://en.wikipedia.org/wiki/LZ4_%28compression_algorithm%29 ) >>>>> is a very fast compression algorithm. In my benchmarks it makes little >>>>> difference to I/O speed, and in general I/O from our in-memory filesystem >>>>> is fast anyhow since it's already in memory. So the downside of needing >>>>> to >>>>> decompress seems small, I don't see much difference in BananaBread >>>>> startup, >>>>> for example, with or without LZ4 compression. >>>>> >>>>> Of course how useful this is depends on how compressible your data is. >>>>> LZ4 can compress text very well, but often data in things like games is >>>>> already compressed, like compressed textures and audio. Still, I saw >>>>> 10%-25% compression on a few games I tried. >>>>> >>>>> Feedback and testing are very welcome. Some docs are at >>>>> >>>>> >>>>> https://github.com/kripken/emscripten/blob/71bf8ed55ed03a96a018f76bf2003acf32db3235/src/settings.js#L250 >>>>> >>>>> but basically just run emcc with -s LZ4=1 . (If you run the file >>>>> packager separately, you need to also pass --lz4 to it.) >>>>> >>>>> - Alon >>>>> >>>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "emscripten-discuss" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to emscripten-discuss+unsubscr...@googlegroups.com. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to emscripten-discuss+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
