Archive activity (ORCL)

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Oracle uses Redo logs to record changes made to a database during operation. These files, which are active or online during normal operation, are referred to as the online redo logfiles. Oracle uses these files to reapply changes made during the recovery process that were not written to datafiles before shutdown. You can operate an Oracle database in ARCHIVELOG or NOARCHIVELOG mode. If you choose ARCHIVELOG mode, then Oracle uses a background process to copy the contents of the online redo logfiles as archive redo logfiles in a separate area. ARCHIVELOG mode lets you perform online backups and database media recovery of your Oracle database.

The Archive Activity Monitor lets you to analyze the status, activity levels, proper sizing and performance of your archive redo logs. At a glance, you can determine the ARCHIVELOG mode, configuration and vital statistics about redo log performance. In particular, the Archive Activity Monitor lets you to assess whether or not the redo logfiles are sized properly. It is very important to choose the right size for online redo logfiles. If the redo logs are too small, the Log Writer must switch logfiles too often, which hurts performance. If the redo logs are too big, recovery times are longer.

The table below describes the Archive Activity Monitor options:

Category Option Description

Log Archiving

Log Mode

Whether or not ARCHIVELOG mode is active for the Oracle instance.

Auto Archival

Whether or not the database has been configured to archive redo logs automatically.


Directory where the archive redo logs are contained.

Oldest Log Sequence

Oldest system change number. As a precaution, your backups should include all archived logfiles starting with the oldest log sequence.

Current Log Sequence

Current system change number. It marks the start of the backup.

Online Redo Archive Activity

Redo Entries

Number entries made to the online redo logs by the Log Writer (LGWR) process.

Avg Redo Size

Average size, in kilobytes, of a redo log entry.

Redo Log Buffer Contention

Entry Requests

Number of entries made to the redo log buffer by the Log Writer (LGWR) process.

Entry Wait Times

Number of times that the Oracle Log Writer has had to wait before making an entry to the redo log buffer. This number is accumulated since the last time that the database was started. A high number of waits indicates that the log buffer size is too small. To increase the size, you need to modify the LOG_BUFFER parameter in the Oracle configuration file (e.g., INITORCL.ORA).

Redo Log Switches


When the redo log switch occurred. If redo log switches occur frequently, the redo logs are probably too small. As a rule-of-thumb, redo log switches should not occur more frequently than once every 30 minutes. If they are occurring more frequently, then you should increase the size of the redo logs.

Record ID in Controlfile

Displays ID number in the control file.

Opening the Archive Activity Dialog Box

  1. On the Utilities menu, click Archive Activity.
    DBArtisan opens the Archive Activity dialog.