From: Christoph Hellwig <hch@infradead.org>
To: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Chris Cottam <chris.cottam@bytemark.co.uk>,
linux-xfs@vger.kernel.org
Subject: Re: XFS reflinks
Date: Tue, 29 Aug 2017 09:23:10 -0700 [thread overview]
Message-ID: <20170829162310.GA22552@infradead.org> (raw)
In-Reply-To: <20170829160308.GR4757@magnolia>
On Tue, Aug 29, 2017 at 09:03:08AM -0700, Darrick J. Wong wrote:
> First, should we land the incore extent map rework (not that I've seen a
> patchset yet) so that the increased extent map fragmentation resulting
> from cow/dedupe don't overwhelm the memory allocator with high order
> allocations? Incore extent map memory usage hasn't been an issue here...
Working on this now, but so far this hasn't been a major issue.
The main workload where the extent list currently hurts and that
prompted my work in this area doesn't even involve reflinks (sparse
VM image).
> Second, regarding realtime + reflink: Right now we don't forbid mounting
> a filesystem with reflink enabled and a realtime device. You can't have
> an inode with both realtime and reflink flags set, so if future xfs
> supports it, old kernels won't totally stumble over those inodes.
> (Though, EFSCORRUPTED is a little rude.) Is that ok? or should we (a)
> make reflink work on realtime devices, (b) complain at mount time, or
> (c) leave everything the way it is?
I think the current situation is fine - if we add reflinks on the RT
device we can just add a ROCOMPAT flag.
next prev parent reply other threads:[~2017-08-29 16:23 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-29 11:23 XFS reflinks Chris Cottam
2017-08-29 13:00 ` Christoph Hellwig
2017-08-29 13:39 ` Chris Cottam
2017-08-29 16:40 ` Christoph Hellwig
2017-08-29 16:03 ` Darrick J. Wong
2017-08-29 16:23 ` Christoph Hellwig [this message]
2017-08-29 22:03 ` Dave Chinner
2017-08-30 7:03 ` Christoph Hellwig
2017-08-31 10:33 ` Chris Cottam
2017-08-31 13:09 ` 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=20170829162310.GA22552@infradead.org \
--to=hch@infradead.org \
--cc=chris.cottam@bytemark.co.uk \
--cc=darrick.wong@oracle.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.