Is Write back cache enabled on physical disks of Perc 6/i ?
dushyanth at gmail.com
Thu Mar 26 12:26:58 CDT 2009
RTFM's a bit and figured the answers
> On 26 Mar 2009, at 16:15, Dushyanth wrote:
> > Christian Rishøj <christian <at> jetment.com> writes:
> >> 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 ?
Write back is enabled only if there is battery available. Refer
Conditions Under Which Write-Back is Employed
Write-back caching is used under all conditions in which the battery is present
and in good condition.
The vdisk property shows the disk cache policy - I have not yet confirmed
whether the Disk Cache policy is also enabled only if a battery is available.
# omreport storage vdisk
List of Virtual Disks in the System
Controller PERC 5/i Adapter (Slot 3)
ID : 0
Status : Ok
Name : RAID1
State : Ready
Progress : Not Applicable
Layout : RAID-1
Size : 465.25 GB (499558383616 bytes)
Device Name : /dev/sda
Type : SATA
Read Policy : No Read Ahead
Write Policy : Write Back
Cache Policy : Not Applicable
Stripe Element Size : 64 KB
Disk Cache Policy : Enabled
More information about the Linux-PowerEdge