Sizing log buffer

Hi All

What are the different ways to size log buffer ?? I am trying to tune the size of log buffer in an OLTP instance with large queris and DML's involving LOB's.


Thanks,

I think one way to get an idea about it's size is to run the utlbstat.sql/utlestat.sql during the time when large queries are being executed. Then check out the report for any Log Buffer waits and then size it accordingly.

Thanks Halo for your suggestion.
Just a real quick question.

Is there a some kind of thumb rule to figure out the size of log buffer before i move on the utlbstat/utlestat ?.



Thanks a lot.

I dont think there is a rule but there is no need to set it very large since lgwr writes

every 3 seconds
every commit
when log buffer is 1/3 full
when log buffer is 1MB full

This means that even you set it very big you will just waste RAM.

I would prbably start with 512K log buffer

Thanks Halo and Pando, Your information is really helpful.
I would do the same.


Thanks