Re: [gentoo-user] Speed up `du'

On Sonntag, 25. Mai 2008, Stroller wrote:
> On 25 May 2008, at 00:24, Willie Wong wrote:
> > On Sat, May 24, 2008 at 04:49:09PM -0500, Penguin Lover
> >
> > reader@×××××××.com squawked:
> >> ...
> >> I use Reiserfs with default sizes.  In some situations like a large
> >> cache of nntp messages of several GB.  I might wait 5-10 minutes
> >> or more
> >> for du to get the size of the directory.
> >
> > I am pretty sure the problem with du is that it actually looks,
> > recursively, at every single file and computes the size that way.
>
> What he said.
>
> > Or maybe there is some other tool or technique that can quickly tell
> > me the size of a directory or set of directories.
>
> Keep all the files in a honkin' big tarball.
>
> :P
>
> If you need to read these files on the fly then I'm afraid you'll
> have to write a kernel filesystem extension (or find one?) that will
> read them out of the tar file, slowing all read & write actions down.
> But, hey, `du` on the tarball will complete in no time at all!! ;)
>
> In seriousness, another thing to do is keep these files on a separate
> partition, if you can. Basically a user's ~ which includes
> both .maildir and "My HiDef Videos" is non-optimal.
>
> >> Are there other file systems that can return a result of `du' faster?
>
> All filesystems have their advantages & disadvantages.
>
> <http://www.debian-administration.org/articles/388>

one thing the article does not mention:

reiserfs and xfs your barriers by default.

ext3 does not. And if you turn on barriers (as mount option) you loose 30% of 
its speed.

Of course, if you care about data integrity, LVM is ruled out too - for the 
same reason.

So if you care about data integrity and speed at the same time, ext3 is ruled 
out.  XFS is broken on a monthly basis (just search the lkml archives for 
xfs. It is sickening). Leaves reiserfs as only sane choice.
-- 
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