[ltp] Filesystem choice?

[Maik Musall]

Hi Buchan,

On Tue, Nov 05, 2002 at 08:30:10PM +0200, Buchan Milne wrote:
> I am running Mandrake 9.0 on a 600X, and I noticed that under
> windows2000, the machine almost never writes to disk when idle (or doing
> simple tasks). However, under Mandrake 9.0, I think I am getting a
> journal write every 10 seconds.
> 
> Since I have a choice of FSs available (Reiser, XFS, ext2, ext3, JFS), I
> was wondering what others would reccomend, in terms of less disk usage
> when idle without sacrificing FS robustness. I guess a journalling FS is
> not so critical on a machine with a built-in UPS, but I still don't like
> ext2 ...

Those periodical writes will occur at least every 30 seconds with all
filesystems as there are many processes looking up some files or
directories periodically which all cause the access time of that
files or directories to be modified. As a consequence, although the
reads of those files or dirs themselves may be completely buffered,
the reads modify the access time of those files which causes flushes
because the modified atime has to be written to the inodes.

You can try to avoid that by specifying the "noatime" option which
nearly all filesystems understand. This will also cause performance
improvements because reads of many files do no longer lead to
as many writes. Just be careful that you do not use a special
application that relies on the atime state.

You can list the atime of files by doing "ls -lu".

By the way, I'm running SuSE 7.2 on my 600X with reiserfs on the
48MB IBM hard disk since several years now, no problems so far, fast
and realiable (use a recent kernel, at least 2.4.18, reiserfs is much
more stable since then). My disk does never spin down however, since
I have disk-intensive applications all the time, and I sometimes
need atime to determine e.g. whether config files had been read by
my application or not.

Regards
-- 
Maik Musall, maik@musall.de, http://www.musall.de
PGP fingerprint: 99 F6 3D F5 BA 42 50 94  01 36 FA A9 27 9D 3C 39