Orion benchmark relationship IOPS v MBPS

From: John Hallas <John.Hallas_at_morrisonsplc.co.uk>
Date: Mon, 8 Feb 2010 14:37:37 +0000
Message-ID: <A92AF970568F9A4BAB18E10F9C64ED6069243616D2_at_EXCH2.morrisonsplc.co.uk>

I suspected we had performance problems with Disk I/O on server B. AWR stats indicated high response times. I therefore ran a fixed Orion benchmark against the server (and some others as well). I ran it against 2 disks and took the best figures from each run. I picked times when the server load was low and re-ran the tests several more times if I suspected that load was higher than other servers.

The backend XP4800 array was the same one in each case bar Server D where the array was remote to the server (in the other tests the server and SAN were on the same site).

The HBA throughput statistics were consistent to the IOPS measurement shown above for each server and HBAs were well balanced across each server.

I am comfortable we have a problem with disk I/O on server B but what I do not understand is why MPBS on server A and server B are almost the same and yet there is a 5fold increase in IOPS on server A.

The test is

 ./orion_hpux_ia64 -run advanced -write 40 -matrix basic -duration 120 -testname mytest -num_disks 2

Server A

Server B

Server C

Server D

MBPS 238




IOPS 13220









XP Array (local)

XP Array (local)

XP Array (local)

XP Array (remote)

Changing the write parameter for Orion to either 10% indicated the same relationship between servers with B performing much worse again.

Any help appreciated in explaining how I can test further or why the IOPS might be so bad on B and yet MBPS has remained roughly the same.


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Received on Mon Feb 08 2010 - 08:37:37 CST

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