From: Neil Brown <neilb@suse.de>
To: Linux Raid Study <linuxraid.study@gmail.com>
Cc: linux-raid@vger.kernel.org
Subject: Re: Raid5 Read stats for parity cal...
Date: Thu, 17 Sep 2009 12:38:48 +1000 [thread overview]
Message-ID: <19121.41272.564725.505554@notabene.brown> (raw)
In-Reply-To: message from Linux Raid Study on Wednesday September 16
On Wednesday September 16, linuxraid.study@gmail.com wrote:
> Hello:
>
> I understand that parity calculations are not done as part of Raid5
> read operation in normal running conditions.
Correct.
>
> However, it would be done during disk failure or when a sector is bad.
Also correct.
> Is there a way (any stats) available to see if parity cal are done
> when sector is bad (since this is not as obvious as a disk fail...)
>
Maybe you want
/sys/block/mdX/md/dev-YYY/errors
which counts the number of sectors for which md found a read error and
had to generate correct data using parity, and then wrote that correct
data back.
NeilBrown
prev parent reply other threads:[~2009-09-17 2:38 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-09-17 0:13 Raid5 Read stats for parity cal Linux Raid Study
2009-09-17 0:20 ` Majed B.
2009-09-17 2:38 ` Neil Brown [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=19121.41272.564725.505554@notabene.brown \
--to=neilb@suse.de \
--cc=linux-raid@vger.kernel.org \
--cc=linuxraid.study@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox