Manually run the checkpoint in Oracle Database
When the Checkpoint occurred, it moves all the dirty buffers to the disk files. Make the buffer cache and data files in a synchronized state. Oracle database ensures all modified buffers are written from the data buffer to disk files and modified the header of the datafiles and control files.
Manually checkpoint in Oracle Database as:
ALTER SYSTEM CHECKPOINT
Automatic checkpoint occurred as:
Following causing automatic checkpoint: 1. Every 3 Seconds. 2. At time of log switch ( Alter system switch logfile) 3. Before begin backup 4. Tablespace offline. 5. fast_start_mttr_target parameter 6. Tablespace Drop 7. ALTER SYSTEM CHECKPOINT ( Manually)