Quote:
Originally Posted by
powerAIX
T
I have already raise request to increase the SGA to 80Gb as memory is of 200Gb.
OK, but prepare to either shrink the LPARs memory or increase the SGA further to about 90% of the available RAM.
The most imminent thing to do, though, is to set the "FILESYSTEMIO_OPTIONS=SETALL" option or to mount the filesystems accordingly. I suggest doing it in the DB configuration: without this you will always have the OS trying to (double-) buffer the DB I/O, which will always be detrimental to performance.
Mounting an FS in CIO-mode (concurrent-I/O) will make all the I/O on that FS be via concurrent I/O, which is a good idea for DB files opened by the DB but a bad idea otherwise. You would need to create separate FSes (not to be mounted with the CIO-option) for i.e. dumps, exports, etc.. Setting the option in the Oracle-config will make the database open the individual files with the CIO-option but the FS itself is not changed. Thiw will have the same effect as above but without the need to create separated FSes.
I hope this helps.
bakunin