Hello Dave! On 05/08/2015 05:55 AM, Dave Chinner wrote: > On Thu, May 07, 2015 at 07:16:02PM +0700, Dewangga wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> Hello Martin, >> Thanks for your reply, yes I've read that link, but another question, >> is noatime,nodiratime,etc still valid for performance tuning guidance? > > You may have read it, but I don't think it sunk in.... > >> Even the default mount options only "rw,inode64,seclabel,attr2". > > Where's relatime(*)? That's been a default for a lot longer than > inode64... > > $ grep "root " /proc/mounts > /dev/root / xfs rw,relatime,attr2,inode64,noquota 0 0 > $ > I forgot write it, but relatime still exists on default mount options. >> Is it still increase the performance if the additional mount options >> added? > > Depends on your workload, which is more critical to understand than > anything else. Why? because it's your workload that is going to > determine if twiddling a knob is going to have any effect on > performance. Once you understand the workload and what the > bottlenecks are, then you can look at what knobs the filesystem > provides to alleviate those bottlenecks. > > IOWs, asking the question "how do I tune my filesystem for best > performance" is, fundamentally, the wrong way to go about obtaining > best filesystem performance. The questions that need to be answered > are "what bottlenecks does my application have?" followed by "what > does the filesystem provide to alleviate those bottlenecks". > > i.e. understand the problem you need to solve *before* you try to > solve it, otherwise you "solve" the wrong problem... > > Cheers, > > Dave. > > (*) An example of exactly what I'm talking abou there. The default > option of relatime gets >95% of the benefit of noatime onmost > workloads compared to the old strictatime behaviour, but unlike > noatime it still retains atime updates. IOWs there's a pretty good > chance that noatime has little measurable impact on your > application's performance, but understanding and benchmarking > anything other than your application won't tell you this. > Okay dave, got it. Standard optimize performance is add mount options like noatime and nodiratime, any additional performance tune is depends on the apps and the workloads. Thanks anyway :) _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
