Oracle performance & bottle necks (redo,rollback and datafiles)

If one is trying to get oracle to perform at its best where should redo logs, rollback segments and datafiles be allocated to.

For example assume it is critical that a mass load must completed within a given time frame.

The box has multiple processors (to take advantage of parallelism) and uses stripping to get flat out performance for the datafiles. But my question is: won't this just shift the bottle next to the redo logs (probably not the rollback segments). If the redo logs have twice the amount of data being written to them (i.e. datafiles and rollback segments) then on a sequential load this will surely be the bottle neck. Writing to the redo logs can't be done in parallel, can it? Putting the redo log files on to a stripped disk may help assuming archiving is switch on (hmmm...I'll think about that one).

Could be really radical and backup the database first then assign the redo logs (and rollback segments) to a null device. If oracle reads from these files then a RAM drive is an alternative.

The same applies to random updates but in this case the datafile processing is slowed down somewhat because of reads, index access etc.

Are there recommendations which state how fast redo logs disks or rollback disk should perform when compared to the datafile disks. Received on Fri Jan 29 1999 - 11:02:12 CST