From: Christoph Hellwig <hch@infradead.org>
To: "Elliott, Robert (Persistent Memory)" <elliott@hpe.com>
Cc: Cholerae Hu <choleraehyq@gmail.com>,
Dan Williams <dan.j.williams@intel.com>,
Dave Chinner <david@fromorbit.com>, Ted Tso <tytso@mit.edu>,
"adilger.kernel@dilger.ca" <adilger.kernel@dilger.ca>,
"linux-nvdimm@lists.01.org" <linux-nvdimm@ml01.01.org>,
"linux-ext4@vger.kernel.org" <linux-ext4@vger.kernel.org>,
"xfs@oss.sgi.com" <xfs@oss.sgi.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: A blocksize problem about dax and ext4
Date: Thu, 24 Dec 2015 02:11:11 -0800 [thread overview]
Message-ID: <20151224101111.GA6438@infradead.org> (raw)
In-Reply-To: <94D0CD8314A33A4D9D801C0FE68B40295BEC9CDD@G9W0745.americas.hpqcorp.net>
On Thu, Dec 24, 2015 at 02:47:07AM +0000, Elliott, Robert (Persistent Memory) wrote:
> > Did you mean that I should make the blocksize bigger until the mount
> > command tell me that dax is enabled?
>
> To really use DAX, the filesystem block size must match the
> system CPU's page size, which is probably 4096 bytes.
No, it doesn't. File you use for DAX must be aligne at page size
granularity. For XFS you could do this with the per-inode extent size
hint for example even if the overall block size is smaller.
next prev parent reply other threads:[~2015-12-24 10:11 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAM=YXF-aXxp19=uFDExUswpEfKXNN6LJScxAB-7-u-AgRiXJ2g@mail.gmail.com>
[not found] ` <CAPcyv4gYHuSWuugnELSO6B1rye+b89io3zJVUXwRt0wE1ZfPrA@mail.gmail.com>
2015-12-23 21:18 ` A blocksize problem about dax and ext4 Elliott, Robert (Persistent Memory)
2015-12-24 0:00 ` Dave Chinner
2015-12-24 0:34 ` Cholerae Hu
2015-12-24 0:58 ` Dan Williams
2015-12-24 2:36 ` Cholerae Hu
2015-12-24 2:47 ` Elliott, Robert (Persistent Memory)
2015-12-24 4:13 ` Cholerae Hu
2015-12-24 10:11 ` Christoph Hellwig [this message]
2015-12-24 12:26 ` Elliott, Robert (Persistent Memory)
2016-01-08 17:22 ` Jeff Moyer
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=20151224101111.GA6438@infradead.org \
--to=hch@infradead.org \
--cc=adilger.kernel@dilger.ca \
--cc=choleraehyq@gmail.com \
--cc=dan.j.williams@intel.com \
--cc=david@fromorbit.com \
--cc=elliott@hpe.com \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvdimm@ml01.01.org \
--cc=tytso@mit.edu \
--cc=xfs@oss.sgi.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;
as well as URLs for NNTP newsgroup(s).