On 06/04, [email protected] wrote: > Hi: > > I've been working on f2fs compression for a while, I'm confused on f2fs > compression performance, after a while reserch, > I found some problem, maybe need some discuss. > I use AndroBench test performance on mobile, after enable compression, the > benchmark scores have dropped a lot. > Specifically: > 1. 32M sequential read has dropped to 50% of original. Test case open file > with O_RDONLY|O_DIRECT, and set POSIX_FADV_RANDOM, the major resaon > is disable readahed. For now,I didn't found any patch can improve this. > 2. 4K random read has dropped to 40% of original, after merge `f2fs: > compress: add compress_inode to cache compressed blocks`, > significant improvement in random read performance, up to 90% of original, > maybe more. > 3. 32M sequential overwrite has dropped to 10% of original, after merge > `f2fs: compress: remove unneeded read when rewrite whole cluster` > up to 30% of original. > 4. 4K random read has dropped to 1% of original, yes only 1% of original, I > found open file with O_WRONLY|O_DSYNC|O_DIRECT is an important reason, > every time sync a compress inode need do checkpoint, after I remove > checkpoint on compress inode, up to 10% of original. And I think major > reason of this > is we need read whole cluster and rewrite it ,but I did't think of any > method to improve this. > > I want to know is there any idea can help to improve this. > And I want to know do we have goal for the performance of compression, is it > possible to achieve the original performance?
Could you please check compress_cache and extent_cache that can improve read performance? Both were done quite recently. > > Thanks. _______________________________________________ Linux-f2fs-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
