[<prev] [next>] [day] [month] [year] [list]
Message-ID: <4EA7C1FD.3090907@tao.ma>
Date: Wed, 26 Oct 2011 16:17:01 +0800
From: Tao Ma <tm@....ma>
To: Amir Goldstein <amir73il@...il.com>
CC: Ted Ts'o <tytso@....edu>,
ext4 development <linux-ext4@...r.kernel.org>,
Andreas Dilger <adilger@...ger.ca>
Subject: Re: [PATCH V1 00/17] ext4: Add inline data support.
On 10/26/2011 04:05 PM, Amir Goldstein wrote:
>
>
> On Wed, Oct 26, 2011 at 9:32 AM, Tao Ma <tm@....ma <mailto:tm@....ma>>
> wrote:
>
> Hi Ted, Andreas and list,
> This is my 1st attempt to add inline data support to ext4
> inode. For
> more information about the background, please refer to the thread
> http://marc.info/?l=linux-ext4&m=131715205428067&w=2
> <http://marc.info/?l=linux-ext4&m=131715205428067&w=2>
> When I sent out the RFC on Sep.27, Andreas suggested that we can use the
> space of xattr to put inline data. So this is the 1st version using that
> method. It should be easy to change if we decide to use other places in
> inode(e.g the unused extent space) since all the inline data
> manipulation function is wrapped with function like ext4_*_inline_data.
>
> Currently I use all the space between i_extra_isize and inode_size if
> inode_size = 256. For inode_size > 256, half of that space is used so as
> to leave some space for other xattrs.
>
> This is only a V1 and there are still something to do(e.g. I am thinking
> of using unused extent space), but I'd like to send it out earlier so
> that it can be reviewed ASAP.
>
> Some simple tests shows that with a linux-3.0 vanilla source, the new
> dir can save 1% disk space. For my "/usr", it can save about 3.2%
> spaces. I guess for volume with future bigalloc support, it should save
> more space for us for small dir. I also run some other tests and it
> seems the code is OK for a try. I haven't found a good test cases that
> can test the small file/dir(tens of bytes in my case) performance where
> inline data should have some good number.
>
> Any comments are welcomed.
>
> git diff --stat
>
> fs/ext4/dir.c | 117 ++++++++++-
> fs/ext4/ext4.h | 15 +-
> fs/ext4/ialloc.c | 4 +
> fs/ext4/inode.c | 583
> +++++++++++++++++++++++++++++++++++++++++++++++---
>
>
> Hi Tao,
>
> One generic comment.
> how about adding a new file fs/ext4/inline.c to host inline data support
> related code?
> inode.c is too big as it is and there is an effort the size it down.
sure, I will try to separate related functions to inline.c in my V2.
Thanks
Tao
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists