Databases
cancel
Showing results for 
Search instead for 
Did you mean: 

A big percentage of WIO while managed recovery

A big percentage of WIO while managed recovery

I have Oracle 8.1.7.3 database in managed recovery mode under HP-UX 11.00 (D390). "sar -u" shows a big percentage of wait IO, more then 50% and a little percentage of system & user loading. Datafiles are placed on 3 grous of hardware raid5 (FC/30). "sar -d" shows average throughtput about 500-800 blocks (max throughtput about 7000). AND DATABASE RESTORES VERY VERY SLOWLY !!!
Any idia/suggestion ?
3 REPLIES
harry d brown jr
Honored Contributor

Re: A big percentage of WIO while managed recovery

Database, or any restore for that matter will be slow. What do you expect the numbers to be?

live free or die
harry
Live Free or Die
Vincent Fleming
Honored Contributor

Re: A big percentage of WIO while managed recovery

You're writing to an old disk array... it's performance is not up to current standards. Your WIO numbers sound typical for your configuration.

Here's two things you can do:

1. check your disk array configuration to make sure you've got it optimally configured for best performance.

2. replace the disk array with a newer, faster disk array. (ie: lots of cache, lots of 15k disks, etc.)

I can't think of much else you could do. You're doing a lot of writing.

Good luck!
No matter where you go, there you are.

Re: A big percentage of WIO while managed recovery

It looks like true. The rate of buzy is more then %50 (in peak up to 100%) and raid groups are loaded irregularly. Probably, it's the matter.