Waits on event "log file sync" while performing COMMIT and ROLLBACK operationsWhat storage type is assigned to redo log groups?
were consuming significant database time.
I want to know what will be the best size of redo logs for my databaseThat purely depends on the amount of redo generated. 3-4 log switches per hour should be ok.
Thread 1 cannot allocate new log, sequence 4234Increase the number of redo log groups.
because these disks are fast so I pointed all database's redo logs to these disksAs these disks were fast, you added everything from everywhere to make them slow.
Can I add the fourth redo log group to the 1st disk again ( even though 1st redo log groupYes, you may create 4th group on the 1st disk, 5th group on the 2nd disk, and 6th group on the 3rd disk.....
is on the same disk) ?
Wed May 14 14:31:00 2008The error basically means, you are switching logfile too fast, Oracle can't prep the previous logfile file group fast enough to be recycled. You might consider add few more redo logfile group. Or resize your redo logfile to bigger size, as you can see the log switch interval is merely 28 seconds.
Thread 1 cannot allocate new log, sequence 4233
Private strand flush not complete
Current log# 3 seq# 4232 mem# 0: /u04/oradata/abc/redo3.log
Thread 1 advanced to log sequence 4233
Current log# 2 seq# 4233 mem# 0: /u03/oradata/abc/redo2.log
Wed May 14 14:31:28 2008
Thread 1 cannot allocate new log, sequence 4234