SURINDER KAPOOR

• Mar 26th, 2006

 

dbw0 The database writer writes modified blocks from the database buffer cache to the datafiles. Oracle Database allows a maximum of 20 database writer processes (DBW0-DBW9 and DBWa-DBWj). The initialization parameter DB_WRITER_PROCESSES specifies the number of DBWn processes. The database selects an appropriate default setting for this initialization parameter (or might adjust a user specified setting) based upon the number of CPUs and the number of processor groups. lgwr The log writer process writes redo log entries to disk. Redo log entries are generated in the redo log buffer of the system global area (SGA), and LGWR writes the redo log entries sequentially into a redo log file. If the database has a multiplexed redo log, LGWR writes the redo log entries to a group of redo log files. KAPOOR

Tarak Nath

• Apr 12th, 2006

 

Increasing the DBWN will not help ,because unless LGWR writes DBWN cannot write. Here the solution will be to decrease th e MTTR parameter  so that frequent check point takes place.