## 28.3. Viewing Locks

[](<>)

Another useful tool for monitoring database activity is the`pg_locks`system table. It allows the database administrator to view information about the outstanding locks in the lock manager. For example, this capability can be used to:

-   View all the locks currently outstanding, all the locks on relations in a particular database, all the locks on a particular relation, or all the locks held by a particular PostgreSQL session.

-   Determine the relation in the current database with the most ungranted locks (which might be a source of contention among database clients).

-   Determine the effect of lock contention on overall database performance, as well as the extent to which contention varies with overall database traffic.

    Details of the`pg_locks`view appear in[Section 52.74](view-pg-locks.html). For more information on locking and managing concurrency with PostgreSQL, refer to[Chapter 13](mvcc.html).