Oracle Tuxedo manages global transactions by maintaining a table of active global transactions and their participants in the Oracle Tuxedo bulletin board called the Global Transaction Table or GTT. As this table is accessed by multiple concurrent processes it must be protected with a semaphore. In the normal Oracle Tuxedo case, the bulletin board lock is used to serialize access to this table. However, under heavy transaction load, the contention for this lock can become substantial resulting in an artificial performance bottleneck.

The bottleneck is eliminated by having a separate lock for each GTT entry.

For more information about configuration, see Introduction to Using Oracle Tuxedo Advanced Performance Pack.