1.type of checkpoint
full checkpoint alter system checkpoint
incrimental checkpoint(logfile switch) alter system switch logfile.
partial checkpoint alter tablespace backup/online/offline
2.phases of instance recovery
1.chek asydatafiles.
2.cache rocovery(roll forward withredo),open database.
3.transaction recovery(roll back uncommited).
4.commited datas in the datafiles.
3.RBA:every three second, checks record the RBA from the oldest entry in the checkopint quene in the control file.only in the event of a log switch,check wirte this formation to the headers of the datafiles.
logfile switch does not force all dirty buffers to be written to disk.
4.Crash recovery is used to recover from a failure either when a single-instance
database crashes or all instances of an Oracle Real Application Clusters database
crashes. Instance recovery refers to the case where a surviving instance recovers a
failed instance in an Oracle Real Application Clusters database.
5.tunning the duration of instance recovery, control the check redo blocks
fast_start_mttr_target
log_checkpoint_timeout
log_checkpoint_interval
fast_start_io_target
v$instance_recovery
v$fast_start_servers
v$fast_start_transactions
6.tunning the phases of the roll forward and roll back
1.recovery_parallelism
2.fast_start_parallel_rollback (false,lo,hi)
3.v$fast_start_servers; v$fast_start_transactions
6.MTTR:mean time to recovery
MTBF:mean time between failures
7.