Messages in this thread | | | Date | Fri, 25 May 2012 18:38:54 +0200 | Subject | Re: atime and filesystems with snapshots (especially Btrfs) | From | Alexander Block <> |
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On Fri, May 25, 2012 at 6:28 PM, Andreas Dilger <adilger@dilger.ca> wrote: > On 2012-05-25, at 9:59, Alexander Block <ablock84@googlemail.com> wrote: > > Are you talking about the atime for the primary copy, or the atime for the snapshots? IMHO, the atime should not be updated for a snapshot unless it is explicitly mounted r/w, or it isn't really a good snapshot. > Snapshots are by default r/w but can be created r/o explicitly. But that doesn't matter for the normal use case where you snapshot / and continue working on /. After snapshotting, all metadata is shared between the two subvolumes, but when a metadata block in one of both subvolume changes (no matter which one), this one metadata block get's cowed and unshared and uses up more space. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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