With only the information provided...

Increase the no. of redo logs. (+2 perhaps)
The same size.

I would test making the log_buffer smaller too
perhaps 512K instead of 5M.
(Just maybe this will help...)

Have Fun


Here is what the doco (ver8 says)

redo log space requests:

The active log file is full and Oracle is waiting for disk space to be allocated for the redo log entries. Space is created by performing a log switch.

Small Log files in relation to the size of the SGA or the commit rate of the work load can cause problems. When the log switch occurs, Oracle must ensure that all committed dirty buffers are written to disk before switching to a new log file. If you have a large SGA full of dirty buffers and small redo log files, a log switch must wait for DBWR to write dirty buffers to disk before continuing.

Also examine the log file space and log file space switch wait events in V$SESSION_WAIT.

redo log space wait time:

The total elapsed time of waiting for redo log space request in 10s of milliseconds.