Locks Event Category

Use the event classes in the Locks event category to monitor locking activity in an instance of the Microsoft SQL Server Database Engine. These event classes can help you investigate locking problems caused by multiple users reading and modifying data concurrently.

Because the Database Engine often processes many locks, capturing the Locks event classes during a trace can incur significant overhead and result in large trace files or tables.

In This Section

Topic	Description
Deadlock Graph Event Class	Provides an XML description of a deadlock.
Lock:Acquired Event Class	Indicates that a lock has been acquired on a resource, such as a row in a table.
Lock:Cancel Event Class	Tracks requests for locks that were canceled before the lock was acquired (for example, to prevent a deadlock).
Lock:Deadlock Chain Event Class	Monitors when deadlock conditions occur and which objects are involved.
Lock:Deadlock Event Class	Tracks when a transaction has requested a lock on a resource already locked by another transaction, resulting in a deadlock.
Lock:Escalation Event Class	Indicates that a finer-grained lock has been converted to a coarser-grained lock.
Lock:Released Event Class	Tracks when a lock is released.
Lock:Timeout (timeout > 0) Event Class	Tracks when lock requests cannot be completed because another transaction has a blocking lock on the requested resource. This event occurs only in situations where the lock time-out value is greater than zero.
Lock:Timeout Event Class	Tracks when lock requests cannot be completed because another transaction has a blocking lock on the requested resource.