Oracle Configuration

Bitrix Site Manager has been tested on Oracle 9i and 10g and showed perfect results.

Using the Oracle database can dramatically improve the system reliability and performance at peak loads. The architecture developed by the Oracle engineers enables administrators to utilize the server power to the full extent achieving perfect interactivity of web applications. With Oracle database, administrators can build web projects of virtually any scale.

Our recommendations on configuring Oracle systems are in general the same specified in the Oracle documentation: reduce read/write, sort and update disk operations.

Pay attention to fine-tuning memory management variables. We recommend using 60% to 80% of system memory for caching:

• db_cache_size
• shared_pool_size
• pga_aggregate_target

For Oracle 10 and later, use Automatic Shared Memory Management:

• At the installation time, set the SGA_MAX_SIZE parameter which specifies the amount of memory (60% to 80%) to be available for the database;
• You can change the Oracle memory pool size at run time by setting the SGA_TARGET parameter. You can derive the proper value experimentally observing the system not performing swap (memory paging) operations. Also check the total swap space used by the system; it should not be more than 100 MB.

In order to save more SGA (shared_pool) space and reduce processor recourses spent for the parsing of SQL queries that differ only in the parameter values, specify cursor_sharing = FORCE or cursor_sharing = SIMILAR. Disable histograms in statistics table columns: begin dbms_stats.set_param('METHOD_OPT', 'FOR ALL COLUMNS SIZE 1' ); end;.

If Oracle and a webs server are installed on the same machine, you can take advantage of using the IPC protocol (PROTOCOL = IPC) and (KEY = EXTPROC) for database connection to avoid communication via the IP stack.

For the two-tier solutions (Front-end and Back-end servers) that define the MaxClients parameter, you can safely use persistent database connections by adding the following instruction:

define("DBPersistent",true);

to /bitrix/php_interface/dbconn.php.

Use delay transactions (Enhanced COMMIT) for Oracle 10g R2 and better. Delay transactions give the system a serious boot by eliminating the influence of disk subsystem performance and reducing the page generation time. To enable delay transactions, set the parameter: COMMIT_WRITE='BATCH,NOWAIT' .