A brief idea about Checkpoint. See Note 147468.1 from Metalink for detail explanation
A Checkpoint is a database event, which synchronizes the data blocks in memory
with the datafiles on disk. A checkpoint has two purposes:
(1) to establish data consistency, and
(2) Enable faster database recovery.
When a checkpoint fails messages must be verified into into the alert.log file.
Here are some tips to tune the checkpoint process:
· The CKPT process can improve performance significantly and decrease the
amount of time users have to wait for a checkpoint operation to complete.
· If the value of LOG_CHECKPOINT_INTERVAL is larger than the size of the redo
log, then the checkpoint will only occur when Oracle performs a log switch
from one group to another, which is preferred. There has been a change in
this behaviour in Oracle 8i.
· The LOG_CHECKPOINTS_TO_ALERT when set to TRUE allows you to log checkpoint
start and stop times in the alert log. This is very helpful in determining
if checkpoints are occurring at the optimal frequency
. Ideally checkpoints should occur only at log swiches