How to define "null-point" before trying to improve performance (VA7400)

[William Wan_1]

This is about HP-UX 11.0 with oracle 8 database using VA7400.

Using armperf I can see a high numbers of read and Write Command Latency for above 20ms, high numbers of disk utilization and yet not very much of data have been transport.

We want to do something ( alot ) to improve the performance. But before that, I want to determinate the current performance of the SAN. Using these information, I should be able to see that some "bottleneck" has been eliminated. What informations are important to collect first before we do any changes in the VA?

I have some idea:
from the ARRAY using armpef to collect
Write / Read Latency, Total IO rate, Write/Read cache Hits.
from the host using messureware to collect
disk utilization, Phys,Log IO rate, requested queue, queue length per disk etc

What else are important too?

Any suggestion, docs, maybe a benchmark prog are very welcome

Thanks in advance

William

[Jean-Luc Oudart]

I suppose you may want to measure same transaction set on the server side. You can measure with the OS (Glance, measureware,sar) and within the Oracle Database Statspack.

Note that when you run the transactions as you have caching in the VA this may alter the results.

Regards,
Jean-Luc

[Jean-Luc Oudart]

Hi William

Also read this document (from HP) on VA performance.
Hope this will be some help for you.

Regards
Jean-Luc

[William Wan_1]

Hi, Jean-Luc,

Great DOC. Where did you found it?
I've been searhing the whole itrc and docs.hp.com for any documentation about VA7400 but couldn't find any. Maybe it's because the VA7400 has already been replaced by VA7410.

I am still looking for specification for the VA7400. Do you have more of these docs?