InfoCenter Home > 6.6.20: Administering transactions (overview)Administrators do not usually need to intervene in server transactions. In fact, an administrator can introduce inconsistencies into server data by forcing a transaction to the wrong outcome. Usually, it is sufficient simply to monitor the progress of transactions. The administrator should become familiar with transaction states, identifiers, and log settings. Circumstances that could require interventionTimeouts associated with transactions usually prevent any one transaction from holding resources at a server for too long. For example, if two transactions are competing for the same resource (one holds a lock on a resource and the other is requesting that lock, and the lock modes conflict), timeouts will eventually abort one of the transactions: the idle timeout will abort a transaction that is inactive too long, and the operation timeout will abort an active transaction that is taking too long. Nevertheless, a transaction can hang indefinitely if, for example, the transaction is prepared but the coordinator is unreachable. If a hung transaction is interfering with the operation of a server (perhaps holding locks that other critical transactions are waiting for), the administrator might need to intervene. An unprepared transaction can be aborted at any time. Unprepared transaction states include active and preparing. Aborting an unprepared transaction does not affect the consistency of data -- the transaction's participants have not yet notified a coordinator of their readiness to commit. If the administrator aborts an unprepared transaction, any work that was completed on behalf of the transaction is rolled back. With transactions that have already prepared, any action that the administrator takes is more significant. It is best to allow the system to resolve the transaction (allow normal processing to take place). However, the administrator will need to force an outcome if a transaction can never be completed otherwise. Enabling in-process transaction loggingYou can improve the throughput of a WebSphere Application Server Advanced Edition installation that makes heavy use of two-phase commitment transactions. Configure the application server to use in-process transaction logging rather than logging through the administrative server, which is the default. To enable in-process transaction logging, set the system property
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