Failure obtaining db row lock: Execution Timeout Expired What this error describes

Quartz.Impl.AdoJobStore.LockException: Failure obtaining db row lock: Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated. ---> System.Data.SqlClient.SqlException: Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated. ---> System.ComponentModel.Win32Exception: The wait operation timed out --- End of inner exception stack trace --- at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption, Boolean shouldCacheForAlwaysEncrypted) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.LockViaUpdate(ConnectionAndTransactionHolder conn, String lockName, String sql) at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.ExecuteSQL(ConnectionAndTransactionHolder conn, String lockName, String expandedSQL, String expandedInsertSQL) --- End of inner exception stack trace --- at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.ExecuteSQL(ConnectionAndTransactionHolder conn, String lockName, String expandedSQL, String expandedInsertSQL) at Quartz.Impl.AdoJobStore.DBSemaphore.ObtainLock(DbMetadata metadata, ConnectionAndTransactionHolder conn, String lockName) at Quartz.Impl.AdoJobStore.JobStoreSupport.ExecuteInNonManagedTXLock[T](String lockName, Func2 txCallback, Func3 txValidator) at Quartz.Impl.AdoJobStore.JobStoreTX.ExecuteInLock[T](String lockName, Func2 txCallback) at Quartz.Core.QuartzScheduler.UnscheduleJobs(IList1 triggerKeys) at .(List1 ) at .(List1 ) at .() [See nested exception: System.Data.SqlClient.SqlException (0x80131904): Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated. ---> System.ComponentModel.Win32Exception (0x80004005): The wait operation timed out at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption, Boolean shouldCacheForAlwaysEncrypted) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.LockViaUpdate(ConnectionAndTransactionHolder conn, String lockName, String sql) at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.ExecuteSQL(ConnectionAndTransactionHolder conn, String lockName, String expandedSQL, String expandedInsertSQL) ClientConnectionId:2e10e680-3426-4a51-bc9c-09cd2dba5e68 Error Number:-2,State:0,Class:11] System.Data.SqlClient.SqlException (0x80131904): Execution Timeout Expired. The timeout period elapsed prior to completion of the operation or the server is not responding. The statement has been terminated. ---> System.ComponentModel.Win32Exception (0x80004005): The wait operation timed out at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) at System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString, Boolean isInternal, Boolean forDescribeParameterEncryption, Boolean shouldCacheForAlwaysEncrypted) at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, Boolean inRetry, SqlDataReader ds, Boolean describeParameterEncryptionRequest) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource1 completion, Int32 timeout, Task& task, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean& usedCache, Boolean asyncWrite, Boolean inRetry) at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.LockViaUpdate(ConnectionAndTransactionHolder conn, String lockName, String sql) at Quartz.Impl.AdoJobStore.UpdateLockRowSemaphore.ExecuteSQL(ConnectionAndTransactionHolder conn, String lockName, String expandedSQL, String expandedInsertSQL) ClientConnectionId:2e10e680-3426-4a51-bc9c-09cd2dba5e68 Error Number:-2,State:0,Class:11