How to improve VA7410 performance

[Dave Chamberlin]

Hello,
I started my VA7410 with 4 luns, later added some disks and added a couple more. Glance is showing very high utilization on "disks" in LUN1 (redundancy group 1). There are no hot spots in LUN2 (redundancy group 2, vg02). I believe I have a severe IO bottleneck in that LUN (vg01 with 4 LVs). During high loads this transfers to CPU bottleneck and the system runs slow. I am thinking to improve IO performance, I can: 1) move hot files from vg01 to vg02 in redundancy group2. 2) after that, the only to improve preformance would be to add more spindles to the array. Is this correct? I am running Oracle 11i and the database is about 125GB. I attached a few screen shots from glance showing the problems...
Thanks

[Dave Chamberlin]

Showing the two hot devices in attached image

[Bill Costigan]

I see the high I/O rates are to LUNs 1 and 3 (I assume they are both in RG 1) why not move one of the LUNs to the other RG group so that they both are balanced.

Create a LUN in RG2 with the same size as LUN 3. add the new LUN to VG01 and do a PV move to move the extents from LUN 3 to the new LUN. Then vgreduce the VG to remove LUN3 from the VG and delete the LUN from the VA.

[Dave Chamberlin]

thanks Bill - I assume that can be done without taking anything down. BTW - will adding more disks to the array improve performance? I currently have 30 disks - if I add 15 more what should I expect? Thanks

[Bill Costigan]

Yes, it can all be done online while the VG is being used. And yes, adding more disks will generally improve performance.

However it will only improve if the va is given multiple I/O to perform at the same time. More disks mean that the va can do more I/Os at the same time.

If an application does a read and then waits for the data before doing the next read, you could add a million disks and not see any increase in performance if that is the only application using the array.

Writes will improve because the va will use write cache which will cause multiple I/Os at the same time. And I guess reads might improve if the read cache hit rate is high. But if there is a high percentage of read cache misses, you are back to a single I/O at a time.

[Bobby Vassallo]

Dave, How do I transfer pictures from my PC to a multimedia card plugged into the 7410? Ideas? bv

bobbyv@san.rr.com

[Bill Costigan]

I don't think your 7410 is a va7410.

va7410s don't have multimedia cards