| Property | Description |
|---|---|
| Parameter type | Integer |
| Default value | 5 MB to 32 MB, depending on the size of the SGA, CPU count, and whether the operating system is 32-bit or 64-bit |
| Modifiable | No |
| Range of values | 2 MB to operating system-dependent |
| Basic | No |
LOG_BUFFER specifies the amount of memory (in bytes) that Oracle uses when buffering redo entries to a redo log file. Redo log entries contain a record of the changes that have been made to the database block buffers. The LGWR process writes redo log entries from the log buffer to a redo log file.
The log buffer size depends on the number of redo strands in the system. One redo strand is allocated for every 16 CPUs and has a default size of 2 MB. Oracle allocates a minimum of 2 redo strands per instance. When the log buffer size is not specified, any remaining memory in the redo granules is given to the log buffer.
See Also:
Oracle Database Performance Tuning Guide for more information on setting this parameter
Your operating system-specific Oracle documentation for the default value and range of values