Foglight 6.3.0 - Performance Tuning Field Guide

Sample init.ora:

Database Maintenance Recommendations

For database maintenance recommendations, see the appropriate sections below.

MySQL Tuning

For more information on MySQL performance, you can try
http://www.mysqlperformanceblog.com and http://www.oracle.com/technetwork/index.html.

Case

Exception: com.quest.nitro.service.topology.LockTimeoutException: Error obtaining cache lock for object

Cause: This exception is thrown when a thread that is trying to update a topology object from a Canonical Data Transformation (CDT), times out waiting for a write lock on the object. If it takes a long time for the object to be updated, it is probably because the database is dealing with a heavy load.

If you run your server in debug mode, the server logs thread and lock information, and therefore reports when it encounters such an error. For example, in one case where this exception was thrown, a thread dump was logged approximately a minute later. That thread dump showed that a few threads were inserting topology objects, and that several threads were waiting for an alarms query to finish. It seemed that the database had been allocated a lot of memory, but it was difficult to tell the status of the I/O. Some configurations are configured to flush the transaction logs to disk at the end of every transaction. The standard, or typical, configuration is more relaxed about this. It sets the following in the my.cnf file:

That setting is beneficial in cases like the one described above.