Re: Application of archived logs on physical standby very slow

Hi Luca et al,

thanks for all your input.
In my case it doesn't seem to be Oracle causing the problem, it's the MSA 1000. I don't know much about its configuration but it seems (to say it in layman's terms) that the storage admins added more disks and grouped them into a disk group. They then carved out 2 logical volumes and presented one of these to the DR box and the other one to production. Now production is terribly busy (the system grows 2-3 GB/day!), and after a reorganisation essentially all IO ends up on that newly added LUN. So this affects all the disks in the disk group on the MSA which in term means slow IO response times for DR. 

Golden rule of not sharing SAN/disks etc violated once more.

Regards,

Martin
--
> Martin Bach
> OCM 10g
> http://martincarstenbach.wordpress.com
> http://www.linkedin.com/in/martincarstenbach

Luca Canali wrote:

Hi,

What do you see in V$RECOVERY_PROGRESS as "Active Apply Rate"? (see also 
discussion in  
http://jarneil.wordpress.com/2008/07/15/monitoring-your-standby-with-vrecovery_progress/)
I have 35655 KB/s on one of my systems for example.

I had a look at the discussion on redo apply tuning in Larry Carpenter's (et al.) book at 
page 119 [one can find it on google books too in case paper in not available :)] they 
mention several diagnostic and tuning techniques, but on the subject of MRP scan/read of 
logs they say "This part of the recovery is easily handled by the single MRP 
process".

Cheers,
L.

PS: in terms of further investigations 
http://www.oracle.com/technology/deploy/availability/pdf/MAA_WP_10gRecoveryBestPractices.pdf
 seems to suggest setting Log_Archive_Trace=8192 for some 'advance 
troubleshooting'



--
http://www.freelists.org/webpage/oracle-l

Other related posts: