RE: Performance issue can't identify

Hi Connie,

You mentioned a problem with copying of large files and that even such a simple task is slow. We have had two problems in the past with that on solaris. The first was the fact that on one solaris box the disks were in a separate disk cabinet. After a lot of complaining to Sun a really bright technician noted that the cache of the disk cabinet (a mere 512MB) was not used at all. When that was configured right a simple test with creating a table from dba_objects several times was reduced in time with a factor of 20. And we had been tuning the database to the hilt before that. A clear case of 'check your bases'.
The second was that there is a mount option for solaris file system called forcedirectio that is bypassing the unix cache for that file system. And I have read some advices this option should be used for all sun-oracle boxes. Turning it on was two times faster or there about. We now use it on all solaris-oracle machines we have.
The second is easier to test, of course:

mount -a|grep forcedirectio

If this outputs no lines for the right (data) filesystems, ask your sysadmin to remount the file systems.

Kind regards,
Eric.

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