Christoph Hello I am testing 2.6.38 with AIM benchmark. I compared 2.6.38 to 2.6.27 and I noticed that 2.6.27 is much better than 2.6.38 when doing sync random writes test over an xfs regular file over native Linux partition on top common sata disk. I git bisected the problem and I reached this SHA1: commit 13e6d5cdde0e785aa943810f08b801cadd0935df Author: Christoph Hellwig <hch@xxxxxx> Date: Mon Aug 31 21:00:31 2009 -0300 xfs: merge fsync and O_SYNC handling The guarantees for O_SYNC are exactly the same as the ones we need to make for an fsync call (and given that Linux O_SYNC is O_DSYNC the equivalent is fdadatasync, but we treat both the same in XFS), except with a range data writeout. Jan Kara has started unifying these two path for filesystems using the generic helpers, and I've started to look at XFS. ... The bellow two tests presents the how different performance is before and patch: #test 16) bisect 11 ------------------------------------------------------------------------------------------------------------ Test Test Elapsed Iteration Iteration Operation Number Name Time (sec) Count Rate (loops/sec) Rate (ops/sec) ------------------------------------------------------------------------------------------------------------ 1 sync_disk_rw 30.71 19 0.61869 1583.85 Sync Random Disk Writes (K)/second ------------------------------------------------------------------------------------------------------------ #test 17 ) bisect 12 ------------------------------------------------------------------------------------------------------------ 1 sync_disk_rw 69.05 1 0.01448 37.07 Sync Random Disk Writes (K)/second ------------------------------------------------------------------------------------------------------------ Regards Raz Ben-Yehuda Reply Reply to all Forward _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
