Changing RAID config on CPG

[joe.benger]

Hi all,

We have a reasonable amount of NL storage free, however we take a hit on the physical disk IO quite consistently. At the moment the CPG is set to use RAID 6 (4+2).

Is there any merit in changing the data number up for an increase in performance (or even changing the RAID type all together)?

Any thoughts?

[Richard Siemers]

What size drives are these? How are your current rebuild times?

[joe.benger]

Hi Richard,

That's a good question, we've only had the array around 1yr and have been lucky enough not to endure any failures yet (touch wood).

At this stage there are 24 x 2TB drives in a single cage.

Thanks.

[3ParDude_1]

I wouldn't bank on getting a lot of performance from your NL disks. When you are designing a system HP best practice is that you don't even count NL disks IOPs when trying to meet your IOPs target. Do you have another tier of storage in your system and AO?

[Cleanur]

Well if you want performance out of them and since they're nearline, why not consider converting them to Raid 1 ?

[Richard Siemers]

We have a 7200 with 24x 3TB drives, but running at Raid6, 6+2.
It was intended for deep capacity and low performance. The app that uses it does mostly sequential reads and writes, and it suits our needs well.

We go out of our way to make sure random workloads get parked on SAS/FC/SSD disk.