From: Dave Chinner <david@fromorbit.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Christoph Hellwig <hch@infradead.org>,
Al Viro <viro@zeniv.linux.org.uk>,
linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
overlayfs <linux-unionfs@vger.kernel.org>
Subject: Re: [GIT PULL] overlayfs update for 4.18
Date: Thu, 31 May 2018 08:27:14 +1000 [thread overview]
Message-ID: <20180530222714.GP23861@dastard> (raw)
In-Reply-To: <CAJfpegvCR4+j0t1dzM=Mvh05JBkz4R5A4Jp=USTtGBeWEL6dGQ@mail.gmail.com>
On Wed, May 30, 2018 at 10:36:46AM +0200, Miklos Szeredi wrote:
> On Tue, May 29, 2018 at 4:12 PM, Miklos Szeredi <miklos@szeredi.hu> wrote:
> > On Tue, May 29, 2018 at 3:59 PM, Christoph Hellwig <hch@infradead.org> wrote:
>
> >>> vfs: export vfs_dedupe_file_range_one() to modules
> >>
> >> Please use EXPORT_SYMBOL_GPL for all these crazy low-level exports.
>
> I'd argue with the "crazy" part. This should have been the primary
> interface from the start. The batched dedupe interface is the crazy
> one:
>
> - deduping is page size granularity at worst; performance would not
> be horrible even if we had to do one syscall per page
> - vast majority of the time it will be file size granularity
>
> Why was that batching invented in the first place?
No idea - the batching ioctl interface is what we inherited from the
btrfs ioctl years ago and there are several dedupe applications out
there that use it. That's why we pulled it up to the vfs rather than
invent a new one and have to wait years for apps to start using
it...
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
next prev parent reply other threads:[~2018-05-30 22:27 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-29 13:21 [GIT PULL] overlayfs update for 4.18 Miklos Szeredi
2018-05-29 13:59 ` Christoph Hellwig
2018-05-29 14:12 ` Miklos Szeredi
2018-05-30 8:36 ` Miklos Szeredi
2018-05-30 22:27 ` Dave Chinner [this message]
2018-06-01 15:26 ` Miklos Szeredi
2018-06-01 16:18 ` Randy Dunlap
2018-06-01 17:03 ` Miklos Szeredi
2018-06-08 12:13 Miklos Szeredi
2018-06-09 6:52 ` Christoph Hellwig
2018-06-09 21:42 ` Linus Torvalds
2018-06-09 23:55 ` Al Viro
2018-06-11 6:09 ` Christoph Hellwig
2018-06-10 5:54 ` Al Viro
2018-06-11 6:10 ` Christoph Hellwig
2018-06-11 8:41 ` Miklos Szeredi
2018-06-11 16:27 ` Christoph Hellwig
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=20180530222714.GP23861@dastard \
--to=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-unionfs@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=viro@zeniv.linux.org.uk \
/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).