On Fri, 25 Dec 2009 at 08:22, Larry McVoy wrote: > Dudes, sync() doesn't flush the fs cache, you have to unmount for that.
Thanks Larry, that was exactly my point[0] too, I should add that to the results page to avoid further confusion or misassumptions: > Well, I do "sync" after each operation, so the data should be on > disk, but that doesn't mean it'll clear the filesystem buffers > - but this doesn't happen that often in the real world too. I realize however that on the same results page the bonnie++ tests were run with a filesize *specifically* set to not utilize the filesystem buffers any more but the measure *disk* performance while my "generic* tests do something else - and thus cannot be compared to the bonnie++ or hdparm results. > No idea if that is still supported, but sync() is a joke for benchmarking. I was using "sync" to make sure that the data "should" be on the disks now, I did not want to flush the filesystem buffers during the "generic" tests. Thanks, Christian. [0] http://www.spinics.net/lists/linux-ext4/msg16878.html -- BOFH excuse #210: We didn't pay the Internet bill and it's been cut off. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
