From: Roman Mamedov <rm@romanrm.net>
To: Wol <antlists@youngman.org.uk>
Cc: Reindl Harald <h.reindl@thelounge.net>,
John Stoffel <john@stoffel.org>,
David T-G <davidtg-robot@justpickone.org>,
Linux RAID list <linux-raid@vger.kernel.org>
Subject: Re: how do i fix these RAID5 arrays?
Date: Sun, 27 Nov 2022 23:08:28 +0500 [thread overview]
Message-ID: <20221127230828.3cfe728b@nvm> (raw)
In-Reply-To: <fd6a2f41-405a-7ec7-e8f1-c970e32973c4@youngman.org.uk>
On Sun, 27 Nov 2022 14:33:37 +0000
Wol <antlists@youngman.org.uk> 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.
--
With respect,
Roman
next prev parent reply other threads:[~2022-11-27 18:08 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-23 22:07 how do i fix these RAID5 arrays? David T-G
2022-11-23 22:28 ` Roman Mamedov
2022-11-24 0:01 ` Roger Heflin
2022-11-24 21:20 ` David T-G
2022-11-24 21:49 ` Wol
2022-11-25 13:36 ` and dm-integrity, too (was "Re: how do i fix these RAID5 arrays?") David T-G
2022-11-24 21:10 ` how do i fix these RAID5 arrays? David T-G
2022-11-24 21:33 ` Wol
2022-11-25 1:16 ` Roger Heflin
2022-11-25 13:22 ` David T-G
[not found] ` <CAAMCDed1-4zFgHMS760dO1pThtkrn8K+FMuG-QQ+9W-FE0iq9Q@mail.gmail.com>
2022-11-25 19:49 ` David T-G
2022-11-28 14:24 ` md RAID0 can be grown (was "Re: how do i fix these RAID5 arrays?") David T-G
2022-11-29 21:17 ` Jani Partanen
2022-11-29 22:22 ` Roman Mamedov
2022-12-03 5:41 ` md vs LVM and VMs and ... (was "Re: md RAID0 can be grown (was ...") David T-G
2022-12-03 12:06 ` Wols Lists
2022-12-03 18:04 ` batches and serial numbers (was "Re: md vs LVM and VMs and ...") David T-G
2022-12-03 20:07 ` Wols Lists
2022-12-04 2:47 ` batches and serial numbers David T-G
2022-12-04 13:54 ` Wols Lists
2022-12-04 13:04 ` batches and serial numbers (was "Re: md vs LVM and VMs and ...") Reindl Harald
2022-12-03 5:41 ` md RAID0 can be grown David T-G
2022-11-25 13:30 ` about linear and about RAID10 (was "Re: how do i fix these RAID5 arrays?") David T-G
2022-11-25 14:23 ` Wols Lists
2022-11-25 19:50 ` about linear and about RAID10 David T-G
2022-11-25 18:00 ` about linear and about RAID10 (was "Re: how do i fix these RAID5 arrays?") Roger Heflin
2022-11-28 14:46 ` about linear and about RAID10 David T-G
2022-11-28 15:32 ` Reindl Harald
[not found] ` <CAAMCDecXkcmUe=ZFnJ_NndND0C2=D5qSoj1Hohsrty8y1uqdfw@mail.gmail.com>
2022-11-28 17:03 ` Reindl Harald
2022-11-28 20:45 ` John Stoffel
2022-12-03 5:58 ` David T-G
2022-12-03 12:16 ` Wols Lists
2022-12-03 18:27 ` David T-G
2022-12-03 23:26 ` Wol
2022-12-04 2:53 ` David T-G
2022-12-04 13:13 ` Reindl Harald
2022-12-04 13:08 ` Reindl Harald
2022-12-03 5:45 ` David T-G
2022-12-03 12:20 ` Reindl Harald
[not found] ` <CAAMCDee_YrhXo+5hp31YXgUHkyuUr-zTXOqi0-HUjMrHpYMkTQ@mail.gmail.com>
2022-12-03 5:52 ` stripe size checking (was "Re: about linear and about RAID10") David T-G
2022-11-25 14:49 ` how do i fix these RAID5 arrays? Wols Lists
2022-11-26 20:02 ` John Stoffel
2022-11-27 9:33 ` Wols Lists
2022-11-27 11:46 ` Reindl Harald
2022-11-27 11:52 ` Wols Lists
2022-11-27 12:06 ` Reindl Harald
2022-11-27 14:33 ` Wol
2022-11-27 18:08 ` Roman Mamedov [this message]
2022-11-27 19:21 ` Wol
2022-11-28 1:26 ` Reindl Harald
2022-11-27 18:23 ` Reindl Harald
2022-11-27 19:30 ` Wol
2022-11-27 19:51 ` Reindl Harald
2022-11-27 14:10 ` piergiorgio.sartor
2022-11-27 18:21 ` Reindl Harald
2022-11-27 19:37 ` Piergiorgio Sartor
2022-11-27 19:52 ` Reindl Harald
2022-11-27 22:05 ` Wol
2022-11-27 22:08 ` Reindl Harald
2022-11-27 22:11 ` Reindl Harald
2022-11-27 22:17 ` Roman Mamedov
2022-11-27 14:58 ` John Stoffel
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