lkml.org 
[lkml]   [2008]   [Feb]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: very poor ext3 write performance on big filesystems?
On Mon, Feb 18, 2008 at 09:16:41AM -0500, Theodore Tso wrote:
> ext3 tries to keep inodes in the same block group as their containing
> directory. If you have lots of hard links, obviously it can't really
> do that, especially since we don't have a good way at mkdir time to
> tell the filesystem, "Psst! This is going to be a hard link clone of
> that directory over there, put it in the same block group".

Hmm, you think such a hint interface would be worth it?

>
> > What has helped a bit was to recreate the file system with -O^dir_index
> > dir_index seems to cause more seeks.
>
> Part of it may have simply been recreating the filesystem, not

Undoubtedly.

> necessarily removing the dir_index feature. Dir_index speeds up
> individual lookups, but it slows down workloads that do a readdir

But only for large directories right? For kernel source like
directory sizes it seems to be a general loss.

-Andi



\
 
 \ /
  Last update: 2008-02-18 15:45    [W:0.373 / U:0.196 seconds]
©2003-2014 Jasper Spaans. Advertise on this site