[Dovecot] bad test with gfs, Is normal?

[Karsten Künne]

On Tuesday 19 February 2008 08:15:44 Antonio Casado Rodríguez imposed 
structure on a
stream of electrons, yielding:
> I've got theses tests, with dovecot 1.0.10, dovecot-lda, quota-maildir
> and maildir.
>
> uname -a
> Linux correo1 2.6.18-53.1.13.el5 #1 SMP Mon Feb 11 13:27:27 EST 2008
> x86_64 x86_64 x86_64 GNU/Linux
> Red Hat Enterprise Linux Server release 5.1 (Tikanga)
>
...
>
> ./imaptest host=127.0.0.1 port=143 user=yyy pass=xxx seed=123 secs=300
>
> 1º TEST.  mailbox in ext3 (disc local), mmap_disible=no
> Totals:
> Logi List Stat Sele Fetc Fet2 Stor Dele Expu Appe Logo
> 100%  50%  50% 100% 100% 100%  50% 100% 100% 100% 100%
>                           30%                  5%
> 1420  710  699 1417 1259 1818  332  996 1259 1411 2832
>
>
> The GFS
> root# fgrep gfs_correo /etc/fstab
> /dev/vgGFSemail/lvGFSemail          /gfs_correo            gfs
> defaults        1 2
>
> 2º TEST mailbox in gfs (disc in SAN), mmap_disable = yes
> Totals:
> Logi List Stat Sele Fetc Fet2 Stor Dele Expu Appe Logo
> 100%  50%  50% 100% 100% 100%  50% 100% 100% 100% 100%
>                           30%                  5%
>  111   48   51  111  103  143   41   78  103  106  222
>
> 2º TEST mailbox in gfs (disc in SAN), mmap_disable = no
> Totals:
> Logi List Stat Sele Fetc Fet2 Stor Dele Expu Appe Logo
> 100%  50%  50% 100% 100% 100%  50% 100% 100% 100% 100%
>                           30%                  5%
>  166   77   85  166  156  213   54  132  156  161  330

Do you mean the performance with GFS is bad? That's about the same thing we 
found out. Sharing the folder space via GFS was terribly slow. We had to 
abandon GFS and switch back to NFS. I believe GFS is just not designed to 
handle a large number of small files and that's what you usually have in your 
mail storage (if you use Maildir).


Karsten.
-- 
Nothing cures insomnia like the realization that it's time to get up.