[Linux-cluster] EXT3 file system runs slow only right after itis mounted

[Bryn M. Reeves]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Brad Filipek wrote:
> Lon,
>  
> No I did not specify any mount options when creating the resource. Any ideas on what would help? 
>  
>  
> Brad Filipek

What's the host doing to the file system just after the mount?

If it's doing lots of directory traversal/stat (e.g. find, du, ls -R
/mount/path etc.) then it's going to be hammering the disks reading in
piles of metadata. If the nodes have a reasonable amount of RAM this'll
all end up cached, making later accesses faster.

If I run a find over one of my large data file systems immediately after
mounting it'll take an order of magnitude or two longer than the same
operation run against the same file system after a few hours of "normal
use".

If you're just reading in data files (and they fit into RAM), then you
might just be seeing the effects of the page cache.

Regards,
Bryn.

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.7 (GNU/Linux)
Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org

iD8DBQFHqbp+6YSQoMYUY94RAvnXAJ9Q/v4ZM2rhkIRDuL8LSbOec4kDqQCfb7++
F0BbA3EL2Vtr33H5BaHfeJI=
=NNEc
-----END PGP SIGNATURE-----