From: Christoph Hellwig <hch@infradead.org>
To: Dave Chinner <david@fromorbit.com>
Cc: "Darrick J. Wong" <djwong@kernel.org>, linux-xfs@vger.kernel.org
Subject: Re: [PATCH 2/8] xfs: separate CIL commit record IO
Date: Thu, 25 Feb 2021 09:34:47 +0100 [thread overview]
Message-ID: <YDdhJ0Oe6R+UXqDU@infradead.org> (raw)
In-Reply-To: <20210224214417.GB4662@dread.disaster.area>
On Thu, Feb 25, 2021 at 08:44:17AM +1100, Dave Chinner wrote:
> > Also, do you have any idea what was Christoph talking about wrt devices
> > with no-op flushes the last time this patch was posted? This change
> > seems straightforward to me (assuming the answers to my two question are
> > 'yes') but I didn't grok what subtlety he was alluding to...?
>
> He was wondering what devices benefited from this. It has no impact
> on highspeed devices that do not require flushes/FUA (e.g. high end
> intel optane SSDs) but those are not the devices this change is
> aimed at. There are no regressions on these high end devices,
> either, so they are largely irrelevant to the patch and what it
> targets...
I don't think it is that simple. Pretty much every device aimed at
enterprise use does not enable a volatile write cache by default. That
also includes hard drives, arrays and NAND based SSDs.
Especially for hard drives (or slower arrays) the actual I/O wait might
matter. What is the argument against making this conditional?
next prev parent reply other threads:[~2021-02-25 8:37 UTC|newest]
Thread overview: 59+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-23 3:34 [PATCH v2] xfs: various log stuff Dave Chinner
2021-02-23 3:34 ` [PATCH 1/8] xfs: log stripe roundoff is a property of the log Dave Chinner
2021-02-23 10:29 ` Chandan Babu R
2021-02-24 20:14 ` Darrick J. Wong
2021-02-25 8:32 ` Christoph Hellwig
2021-03-01 15:13 ` Brian Foster
2021-02-23 3:34 ` [PATCH 2/8] xfs: separate CIL commit record IO Dave Chinner
2021-02-23 12:12 ` Chandan Babu R
2021-02-24 20:34 ` Darrick J. Wong
2021-02-24 21:44 ` Dave Chinner
2021-02-24 23:06 ` Darrick J. Wong
2021-02-25 8:34 ` Christoph Hellwig [this message]
2021-02-25 20:47 ` Dave Chinner
2021-03-01 9:09 ` Christoph Hellwig
2021-03-03 0:11 ` Dave Chinner
2021-02-26 2:48 ` Darrick J. Wong
2021-02-28 16:36 ` Brian Foster
2021-02-28 23:46 ` Dave Chinner
2021-03-01 15:33 ` Brian Foster
2021-03-01 15:19 ` Brian Foster
2021-03-03 0:41 ` Dave Chinner
2021-03-03 15:22 ` Brian Foster
2021-03-04 22:57 ` Dave Chinner
2021-03-05 0:44 ` Dave Chinner
2021-02-23 3:34 ` [PATCH 3/8] xfs: move and rename xfs_blkdev_issue_flush Dave Chinner
2021-02-23 12:57 ` Chandan Babu R
2021-02-24 20:45 ` Darrick J. Wong
2021-02-24 22:01 ` Dave Chinner
2021-02-25 8:36 ` Christoph Hellwig
2021-02-23 3:34 ` [PATCH 4/8] xfs: async blkdev cache flush Dave Chinner
2021-02-23 5:29 ` Chaitanya Kulkarni
2021-02-23 14:02 ` Chandan Babu R
2021-02-24 20:51 ` Darrick J. Wong
2021-02-23 3:34 ` [PATCH 5/8] xfs: CIL checkpoint flushes caches unconditionally Dave Chinner
2021-02-24 7:16 ` Chandan Babu R
2021-02-24 20:57 ` Darrick J. Wong
2021-02-25 8:42 ` Christoph Hellwig
2021-02-25 21:07 ` Dave Chinner
2021-02-23 3:34 ` [PATCH 6/8] xfs: remove need_start_rec parameter from xlog_write() Dave Chinner
2021-02-24 7:17 ` Chandan Babu R
2021-02-24 20:59 ` Darrick J. Wong
2021-02-25 8:49 ` Christoph Hellwig
2021-02-25 20:55 ` Dave Chinner
2021-02-23 3:34 ` [PATCH 7/8] xfs: journal IO cache flush reductions Dave Chinner
2021-02-23 8:05 ` [PATCH 7/8 v2] " Dave Chinner
2021-02-24 12:27 ` Chandan Babu R
2021-02-24 20:32 ` Dave Chinner
2021-02-24 21:13 ` Darrick J. Wong
2021-02-24 22:03 ` Dave Chinner
2021-02-25 4:09 ` Chandan Babu R
2021-02-25 7:13 ` Chandan Babu R
2021-03-01 5:44 ` Dave Chinner
2021-03-01 5:56 ` Dave Chinner
2021-02-25 8:58 ` Christoph Hellwig
2021-02-25 21:06 ` Dave Chinner
2021-03-01 19:29 ` Brian Foster
2021-02-23 3:34 ` [PATCH 8/8] xfs: Fix CIL throttle hang when CIL space used going backwards Dave Chinner
2021-02-24 21:18 ` Darrick J. Wong
2021-02-24 22:05 ` Dave Chinner
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=YDdhJ0Oe6R+UXqDU@infradead.org \
--to=hch@infradead.org \
--cc=david@fromorbit.com \
--cc=djwong@kernel.org \
--cc=linux-xfs@vger.kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).