SmartArray Performance Optimisation/Bottleneck

[Wesley W.D. Summers]

I have noticed that the Smart-2, SA3200 & SA4200 Smart Array controllers that I have all seem to Read/Write SEQUENTIALLY to the SAME Channel, THEN Swap to the OTHER Channel.

If there are 7 drives on each channel, this approach would have the potential to cause significant performance bottlenecks.

If you swap every second disk drive from one channel to the other (of a 2-channel setup), you can see the controller swapping channels, so that every second I/O is on the other channel.

Can anyone offer any insight to the decision to perform I/O on the same channel for (say) 7 different drives, then do another 7 on another channel?

Can anyone point me in the direction of a White Paper on the best way to set up Smart Array controllers for optiumum performance?


Regards, Wesley.
(Check my profile - I allocate points!)

[Benjamin W. Hill_1]

Wesley,

Try the whitepapaper at this URL
http://h200001.www2.hp.com/bc/docs/support/UCR/SupportManual/TPM_ecg0250997/TPM_ecg0250997.pdf

It helped me to understand the various configurations and how they affected performance.

Regards,

Ben

[Wesley W.D. Summers]

Thanks for the URL Ben. I have scanned it quickly while it was printing, and I will let you know if it gives me the detail that I need.

There WAS a section on overlaying Disk I/O, but I didn't look at it in enough detail to determine if it describes HOW to achieve that overlaying with a Smart Array controller.

I should be able to get back to you within the next 24 hours.


Regards, Wesley.