Which version of Oracle? Oracle isn't very aggressive doing logswitch checkpoints anymore. You can easily test it out by having 3-4 redolog groups, doing logswitches and querying groups which have status = ACTIVE from v$log. The ACTIVE groups haven't checkpointed to disk yet. In 9i at least one log group was allowed to stay ACTIVE after log switch without initiating a checkpoint, in 10gR2 all my 4 logfile groups were not checkpointed by default (had 1 CURRENT and 3 ACTIVE groups). But on next logswitch all three ACTIVE groups were checkpointed. Tanel. ----- Original Message ----- From: LS Cheng To: oracle-l@xxxxxxxxxxxxx Sent: Tuesday, May 23, 2006 6:40 PM Subject: checkpoint over 15 minutes? Hi I have a piece of alert.log, as follows: If I understand well the checkpoint SCN: 0x0336.77684e1c took 16 minutes???