Am 27.11.22 um 20:21 schrieb Wol:
On 27/11/2022 18:08, Roman Mamedov wrote:
On Sun, 27 Nov 2022 14:33:37 +0000
Wol <antlists@xxxxxxxxxxxxxxx> wrote:
If raid supports trim, that means it intercepts the trim commands, and
uses it to keep track of what's being used by the layer above.
In other words, if the filesystem is only using 10% of the disk,
supporting trim means that raid knows which 10% is being used and only
bothers syncing that!
Not sure which RAID system you are speaking of, but that's not presently
implemented in mdadm RAID. It does not use TRIM of the array to keep
track of
unused areas on the underlying devices, to skip those during rebuilds.
And I
am unaware of any other RAID that does. Would be nice to have though.
Yup that's what I was saying - it would very much be a "nice to have"
you clearly need to distinct "nice to have" vesus "state of play" -
nobody gain anything from nice to have when the topic are *existing*
differences
what is "nice to have" for mdadm is "exists in ZFS/BTRFS"
