Locks Event Category

THIS TOPIC APPLIES TO: yesSQL ServeryesAzure SQL DatabasenoAzure SQL Data Warehouse noParallel Data Warehouse

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.