2016-02-23 17:55 GMT+01:00 Nazar Mokrynskyi <na...@mokrynskyi.com>: >> > 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. =:^) > > Well, then I'll leave relatime on root fs and noatime on partition with > snapshots, thanks.
If you snapshot the root filesystem then the atime changes will still be there, and you'll be having a lot of unnecessary changes between each snapshot. > Sincerely, Nazar Mokrynskyi > github.com/nazar-pc > Skype: nazar-pc > Diaspora: naza...@diaspora.mokrynskyi.com > Tox: > A9D95C9AA5F7A3ED75D83D0292E22ACE84BA40E912185939414475AF28FD2B2A5C8EF5261249 > > -- 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
