From: Christoph Hellwig <hch@infradead.org>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Bernd Schubert <bschubert@ddn.com>,
axboe@kernel.dk, io-uring@vger.kernel.org,
linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org,
linux-xfs@vger.kernel.org, dsingh@ddn.com
Subject: Re: [PATCH 1/2] fs: add FMODE_DIO_PARALLEL_WRITE flag
Date: Thu, 13 Apr 2023 22:11:28 -0700 [thread overview]
Message-ID: <ZDjggMCGautPUDpW@infradead.org> (raw)
In-Reply-To: <CAJfpegt_ZCVodOhQCzF9OqKnCr65mKax0Gu4OTN8M51zP+8TcA@mail.gmail.com>
On Thu, Apr 13, 2023 at 09:40:29AM +0200, Miklos Szeredi wrote:
> fuse_direct_write_iter():
>
> bool exclusive_lock =
> !(ff->open_flags & FOPEN_PARALLEL_DIRECT_WRITES) ||
> iocb->ki_flags & IOCB_APPEND ||
> fuse_direct_write_extending_i_size(iocb, from);
>
> If the write is size extending, then it will take the lock exclusive.
> OTOH, I guess that it would be unusual for lots of size extending
> writes to be done in parallel.
>
> What would be the effect of giving the FMODE_DIO_PARALLEL_WRITE hint
> and then still serializing the writes?
I have no idea how this flags work, but XFS also takes i_rwsem
exclusively for appends, when the positions and size aren't aligned to
the block size, and a few other cases.
next prev parent reply other threads:[~2023-04-14 5:11 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-07 17:20 [PATCHSET for-next 0/2] Flag file systems as supporting parallel dio writes Jens Axboe
2023-03-07 17:20 ` [PATCH 1/2] fs: add FMODE_DIO_PARALLEL_WRITE flag Jens Axboe
2023-04-12 13:40 ` Bernd Schubert
2023-04-12 13:43 ` Bernd Schubert
2023-04-13 7:40 ` Miklos Szeredi
2023-04-13 9:25 ` Bernd Schubert
2023-04-14 5:11 ` Christoph Hellwig [this message]
2023-04-14 15:36 ` Darrick J. Wong
2023-04-15 13:15 ` Jens Axboe
2023-04-18 12:42 ` Miklos Szeredi
2023-04-18 12:55 ` Bernd Schubert
2023-04-18 22:13 ` Dave Chinner
2023-04-19 1:28 ` Jens Axboe
2023-04-16 5:54 ` Christoph Hellwig
2023-04-19 1:29 ` Jens Axboe
2023-03-07 17:20 ` [PATCH 2/2] io_uring: avoid hashing O_DIRECT writes if the filesystem doesn't need it Jens Axboe
2023-03-15 17:40 ` [PATCHSET for-next 0/2] Flag file systems as supporting parallel dio writes Jens Axboe
2023-03-16 4:29 ` Darrick J. Wong
2023-03-17 2:53 ` Jens Axboe
2023-04-03 12:24 ` Christian Brauner
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=ZDjggMCGautPUDpW@infradead.org \
--to=hch@infradead.org \
--cc=axboe@kernel.dk \
--cc=bschubert@ddn.com \
--cc=dsingh@ddn.com \
--cc=io-uring@vger.kernel.org \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-xfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
/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).