Is Write back cache enabled on physical disks of Perc 6/i ?

[Christian Rishøj]

On 26 Mar 2009, at 11:32, Dushyanth wrote:

>> Any pointers/suggestions would be of great help.
>
> Does anyone know if write back cache is enabled on the physical  
> disks of
> Perc 6/I controllers ?

Our server came from Dell with disk caches disabled. We saw a small  
performance gain by enabling it ourselves.

You can inspect the configuration with omreport. E.g.:

$ sudo omreport storage vdisk
List of Virtual Disks in the System

Controller PERC 6/i Integrated (Embedded)
ID                  : 0
Status              : Ok
Name                : Virtual Disk 0
State               : Ready
Progress            : Not Applicable
Layout              : RAID-5
Size                : 272.25 GB (292326211584 bytes)
Device Name         : /dev/sda
Type                : SAS
Read Policy         : Adaptive Read Ahead
Write Policy        : Write Back
Cache Policy        : Not Applicable
Stripe Element Size : 64 KB
Disk Cache Policy   : Enabled <===

With best regards

Christian