Separate user log cache for a session’s tempdb

Previous versions of Adaptive Server flushed the user log cache (ULC) as user sessions switched between transactions in the user databases and tempdb database. However, flushing the ULC causes logical IOs in syslogs and disk IOs, causing performance degradation.

Adaptive Server version 15.0.2 includes a separate ULC for the session’s temporary database, so multi-database transactions that include a single user database and the session’s temporaroy database do not require ULC flushes when the users switch between the databases or if all of the following conditions are met:

• Adaptive Server is currently committing the transaction.

• All the log records are in the ULC

• There are no post-commit log records.

Adaptive Server version 15.0.2 adds the configuration option, session tempdb log cache size, which allows you to configure the size of the ULC, helping to determine how often it needs flushing.