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XP512 Disk I/O issues

XP512 Disk I/O issues

I am new to this system and have been informed that there is a large report job that runs on the system which is taking a lot longer to complete than it should. The issue seems to be disk I/O, while investigating I noticed that cache Lun is not initialised and am wondering if initialising this would improve disk I/O performance?

Thanks in advance
3 REPLIES
Chris Callihan_1
Frequent Advisor

Re: XP512 Disk I/O issues

cache lun is a licensed feature (costs extra if you have not already purchased). it allows you to lock an entire lun into the array's cache. but this would take cache that the array manages in the manner it feels would give best performance, but that probably would not even be an option, i will guess that the size of the luns being accessed for you report job are larger than the cache in the array to begin with. even if it wasn't, i would not recommend this approach (or at least have a LOT more information before i pursued that path)
Dave La Mar
Honored Contributor

Re: XP512 Disk I/O issues

Tom-
If you have Measureware installed, you can use metrics and adviser only to monitor your i/o.
Even without cacheing, you might be able to better balance access to the luns via the pvlinks at the o/s level.
It is entirely possible the response time is due to an imbalance in the pathing to luns involved.

Regards,

-dl
"I'm not dumb. I just have a command of thoroughly useless information."

Re: XP512 Disk I/O issues

Thanks for the replies,
It seems the problem is the application and the large volume of data the report job needs to access. As a precaution a HP engineer is coming to check the system to ensure there are no issues with the system.

Thanks