Nazar Mokrynskyi posted on Mon, 22 Feb 2016 20:58:45 +0100 as excerpted: > What is wrong with noatime,relatime? I'm using them for a long time as > good compromise in terms of performance.
The one option ends up canceling the other, as they're both atime related options that say do different things. I'd have to actually setup a test or do some research to be sure which one overrides the other (but someone here probably can say without further research), tho I'd /guess/ the latter one overrides the earlier one, which would effectively make them both pretty much useless, since relatime is the normal kernel default and thus doesn't need to be specified. Noatime is strongly recommended for btrfs, however, particularly with snapshots, as otherwise, the changes between snapshots can consist mostly of generally useless atime changes. (FWIW, after over a decade of using noatime here (I first used it on the then new reiserfs, after finding a recommendation for it on that), I got tired of specifying the option on nearly all my fstab entries, and now days carry a local kernel patch that changes the default to noatime, allowing me to drop specifying it everywhere. I don't claim to be a coder, let alone a kernel level coder, but as a gentooer used to building from source for over a decade, I've found that I can often find the code behind some behavior I'd like to tweak, and given good enough comments, I can often create trivial patches to accomplish that tweak, even if it's not exactly the code a real C coder would choose to use, which is exactly what I've done here. So now, unless some other atime option is specified, my filesystems are all mounted noatime. =:^) -- 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
