The checkpoint (CKPT) process frees up limited memory space and ensures instance recovery. It is a background process that monitors the number of dirty buffers that have not been written to disk. Depending on the LOG_CHECKPOINT_INTERVAL parameter, it also gives the DBWR a wakeup call to write dirty buffer to disk. At a specified time, it updates all the data and control files with the new log file control number. This process is optionally enabled if parameter CHECKPOINT_PROCESS contains a TRUE value
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partho
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The checkpoint (CKPT) process frees up limited memory space and ensures instance recovery. It is a background process that monitors the number of dirty buffers that have not been written to disk. Depending on the LOG_CHECKPOINT_INTERVAL parameter it also gives the DBWR a wakeup call to write dirty buffer to disk. At a specified time it updates all the data and control files with the new log file control number. This process is optionally enabled if parameter CHECKPOINT_PROCESS contains a TRUE value
checkpoint is a background process which ensures dbwn process has written data to datafiles and upadates control file and datafile header to establish data consistency
Each time logswitch occurs then time ckpt occurs and when shutdowning the database that time occurs the ckpt gives the signal to DBWn. The DBWn writes from data buffer cache to datafile.
checkpoint is backgroud process. it'll occur in some situations like during log switch or on the basis of log_checkpoint_interval or log_checkpoint_timeout parameter in parameter file.
checkpoint process will synchronize the logfiles datafiles and update the controlfile information. there are some data in dirty buffer whos corresponding log entries are already in logfile. ckpt check this status ask dbwr to write dirty buffer data to datafiles and also updates controlfile with latest SCN.
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