1. Log_buffer Is An Auto-tuned Parameter Analysis
2. Log_buffer Is An Auto-tuned Parameter Code
3. Log_buffer Is An Auto-tuned Parameter Number
4. Log_buffer Is An Auto-tuned Parameters

Oracle Architecture and Adminstration. The size of the redo log buffer is determined by the LOGBUFFER initialization parameter. In Oracle 10g, the SHAREDPOOLSIZE, LARGEPOOLSIZE, JAVAPOOLSIZE and DBCACHESIZE are known as the auto-tuned SGA parameters. If you set the value for SGATARGET to a value greater than zero then the. LOGBUFFER = 200M You issue the following command to increase the value of DB8KCACHESIZE: SQL ALTER SYSTEM SET DB8KCACHESIZE=140M; Which statement is true? It fails because the DB8KCACHESIZE parameter cannot be changed dynamically. It succeeds only if memory is available from the autotuned components if SGA.

Log_buffer Is An Auto-tuned Parameter Analysis

Automatic shared memory management simplifies the configuration of the SGA by automatically distributing the memory in the SGA for the following memory pools:

• Database buffer cache (default pool)

• Shared pool

• Large pool

• Java pool

• Streams pool

Log_buffer Is An Auto-tuned Parameter Code

Automatic shared memory management is controlled by the SGA_TARGET parameter. Changes in the value of the SGA_TARGET parameter automatically resize these memory pools. If these memory pools are set to nonzero values, then automatic shared memory management uses these values as minimum levels. Oracle recommends that you set the minimum values based on the minimum amount of memory an application component requires to function properly.

The following memory caches are manually-sized components and are not controlled by automatic shared memory management:

• Redo log buffer

  The redo log buffer is sized using the LOG_BUFFER initialization parameter, as described in 'Configuring the Redo Log Buffer'.

• Other buffer caches (such as KEEP, RECYCLE, and other nondefault block size) Cooking girl games download.

  The KEEP pool is sized using the DB_KEEP_CACHE_SIZE initialization parameter, as described in 'Configuring the KEEP Pool'.

  The RECYCLE pool is sized using the DB_RECYCLE_CACHE_SIZE initialization parameter, as described in 'Configuring the RECYCLE Pool'.

• Fixed SGA and other internal allocations

  Fixed SGA and other internal allocations are sized using the DB_nK_CACHE_SIZE initialization parameter.

The memory allocated to these memory caches is deducted from the value of the SGA_TARGET parameter when automatic shared memory management computes the values of the automatically-tuned memory pools.

Log_buffer Is An Auto-tuned Parameter Number

The following sections describe how to access and set the value of the SGA_TARGET parameter:

See Also:

Log_buffer Is An Auto-tuned Parameters

• Oracle Database Concepts for information about the SGA

• Oracle Database Administrator's Guide for information about managing the SGA

• Oracle Database Administrator's Guide for information about using initialization parameters

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:

• Your operating system-specific Oracle documentation for the default value and range of values

• Oracle Streams Replication Administrator's Guide for information on using this parameter in an Oracle Streams environment

• Oracle Database Performance Tuning Guide for information on resizing the redo log buffer using this parameter