Enabling the database as a JTA resource manager alters database processing in the following ways:

• Crash recovery — Crash recovery processing executes every time a database is started, whether in single-user or multi-user mode. A JTA enabled database must perform crash recovery in multi-user mode. Attempting to perform crash recovery in single user mode results in an error if any JTA transactions exist in at startup in a prepared state.
• Roll forward recovery — After-image files written by a JTA-enabled database, must be applied to a JTA-enabled database. In addition, the endtime and endtrans options for ROLL FORWARD are not allowed.
• Before-image processing — Long running JTA transactions prevent reuse of before-image clusters.