From: Dave Chinner <david@fromorbit.com>
To: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org
Subject: Re: [RFC] fadvise: add more flags to provide a hint for block allocation
Date: Wed, 7 Mar 2012 11:51:30 +1100 [thread overview]
Message-ID: <20120307005130.GH3592@dastard> (raw)
In-Reply-To: <20120305125029.GA5121@gmail.com>
On Mon, Mar 05, 2012 at 08:50:29PM +0800, Zheng Liu wrote:
> Hi list,
>
> Block allocation is a key component of file system. Every file systems try to
> improve the performance with optimizing the block allocation of a file. But no
> matter what file system does, it just guesses what the user expects. Thus, it
> is not very accurate. fadvise(2) provides a method to let the user to give a
> hint to file system. However, until now, only few flags are provided. So we
> can provide more flags to tell file system how to allocate the blocks for a
> file.
>
> For example:
> we can add these flags into fadvise(2):
> FADV_ALLOC_READ_SEQ
fallocate()
> FADV_ALLOC_READ_RANDOM
Allocation can't be optimised as the read pattern cannot be defined.
> FADV_ALLOC_WRITE_ONCE
fallocate()
> FADV_ALLOC_WRITE_APPEND
chattr +a
Cheers,
Dave.
--
Dave Chinner
david@fromorbit.com
next prev parent reply other threads:[~2012-03-07 0:51 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-05 12:50 [RFC] fadvise: add more flags to provide a hint for block allocation Zheng Liu
2012-03-05 19:48 ` Sunil Mushran
2012-03-06 2:35 ` Zheng Liu
2012-03-06 4:26 ` Sunil Mushran
2012-03-06 13:30 ` Zheng Liu
2012-03-06 8:27 ` Lukas Czerner
2012-03-06 13:56 ` Zheng Liu
2012-03-06 14:29 ` Lukas Czerner
2012-03-06 17:53 ` Sunil Mushran
2012-03-07 8:51 ` Lukas Czerner
2012-03-07 17:11 ` Ted Ts'o
2012-03-07 0:51 ` Dave Chinner [this message]
2012-03-07 4:14 ` Andreas Dilger
2012-03-07 5:02 ` Martin K. Petersen
2012-03-07 12:11 ` Dave Chinner
2012-03-08 4:23 ` Martin K. Petersen
2012-03-08 7:07 ` Dave Chinner
2012-03-08 17:01 ` Martin K. Petersen
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=20120307005130.GH3592@dastard \
--to=david@fromorbit.com \
--cc=linux-ext4@vger.kernel.org \
--cc=linux-fsdevel@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.