Mitchell Fossen posted on Wed, 25 Nov 2015 15:49:58 -0600 as excerpted: > Also, is there a recommendation for relatime vs noatime mount options? I > don't believe anything that runs on the server needs to use file access > times, so if it can help with performance/disk usage I'm fine with > setting it to noatime.
FWIW I finally got tired enough of always setting noatime (for over a decade, since kernel 2.4 and my standardizing to then reiserfs) that I finally found the spot in the kernel where the relatime default is set, and patched it to be noatime by default. My kernel scripts apply that on top of my git kernel pulls, now. For people doing snapshotting in particular, atime updates can be a big part of the differences between snapshots, so it's particularly important to set noatime if you're snapshotting. If you're not doing snapshots, it's somewhat less important, but IIRC it was still someone more of a performance issue than with ext*, tho I don't remember the details but I'd guess it's to do with COWing the metadata triggering metadata fragmentation. Bottom line, use noatime unless you have something that needs atime. It's not going to hurt for sure, and should improve performance at least somewhat even on ext*. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman -- 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
