PowerEdge 2900 (PERC 6/i) very slow on disk writing.

[Gido_Baumann at Dell.com]

Hi Benedito,

thanks for the output.

Cause of CentOS 5.2 XEN kernel I am not sure if this will improve the
speed in every case,
but it was helpful in the past. Please keep in mind to backup your
system and / or test all
steps in a test environment before.

The steps:

- performed NVRAM clear, which will reset all BIOS settings

- updated BIOS from 2.5.0 to actual version 2.6.1

- replaced megasas 00.00.03.15-RH1 with 03.21-06 or 04.01 version
  (this was possible via DKMS driver packet provided from DELL download
page  
   or take them from newer XEN kernel)

- replaced bnx2 v1.6.9 with v.1.8.x or higher version
  (this was possible via DKMS driver packet provided from DELL download
page 
   or take them from newer XEN kernel or directly from Broadcom download
page)

For driver update you will need kernel-sources, gcc, build environment
and so on ...

- maybe it is necessary to update PERC6I firmware too

After this performance was significant improved.

> eight disks (RAID 5),
> two logical disks (one is 300G for system,
> other is 6T, storing a bunch of images).

Here could be a other RAID design be faster. Maybe it is possible to
test this.
Are you using LVM? 
 
Regards