c# - SqlException 事务在通信缓冲区资源上被死锁

Question

我有一个必须执行大量数据库查询的服务器进程，它使用 TPL 并行运行。它今年一整年都运行良好，直到今天它在 30 分钟内崩溃了两次，但出现以下异常:

Transaction (Process ID 89) was deadlocked on communication buffer resources with another process and has been chosen as the deadlock victim. Rerun the transaction.

数据库被配置为记录任何死锁，但它没有记录任何东西，所以这个死锁似乎只发生在客户端？

除了一个 msdn forum post that doesn't provide any information 之外，我找不到任何对此异常的引用.

有没有人见过这个异常？或者知道我可以做些什么来找到更多相关信息？

---> System.AggregateException: One or more errors occurred. 

---> System.Data.SqlClient.SqlException: Transaction (Process ID 89) was deadlocked on communication buffer resources with another process and has been chosen as the deadlock victim. Rerun the transaction.
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.HasMoreRows()
   at System.Data.SqlClient.SqlDataReader.ReadInternal(Boolean setTimeout)
   at App.CoreEngine.V5.DataAccess.SqlReader.Read(String readerDescription) in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\SqlReader.cs:line 121
   at App.CoreEngine.V5.DataAccess.DataContext.ExecuteQuery(PtQuery query, ValueStore`1 store, String readerDescription) in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 328
   at App.CoreEngine.V5.DataAccess.DataContext.<>c__DisplayClass12.<GetCalculatedDataForCompare>b__f(Object _) in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 267
   at System.Threading.Tasks.Task.Execute()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.WaitAll(Task[] tasks, Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at App.CoreEngine.V5.DataAccess.DataContext.GetCalculatedDataForCompare() in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 276
   at System.Threading.Tasks.Task`1.InvokeFuture(Object futureAsObj)
   at System.Threading.Tasks.Task.Execute()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.Wait(Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at System.Threading.Tasks.Task`1.get_Result()
   at App.CoreEngine.V5.DataAccess.DataContext.get_CalcCompareData() in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 389
   at App.CoreEngine.V5.Calculation.CalculationEngine.Run() in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\Calculation\CalculationEngine.cs:line 243
   at App.CoreEngine.V5.Processor.Milestone.BatchRunner.Run() in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\Processor\Milestone\BatchRunner.cs:line 171

---> (Inner Exception #0) System.AggregateException: One or more errors occurred. 
---> System.Data.SqlClient.SqlException: Transaction (Process ID 89) was deadlocked on communication buffer resources with another process and has been chosen as the deadlock victim. Rerun the transaction.
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning()
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlDataReader.HasMoreRows()
   at System.Data.SqlClient.SqlDataReader.ReadInternal(Boolean setTimeout)
   at App.CoreEngine.V5.DataAccess.SqlReader.Read(String readerDescription) in C:\SourceCode\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\SqlReader.cs:line 121
   at App.CoreEngine.V5.DataAccess.DataContext.ExecuteQuery(PtQuery query, ValueStore`1 store, String readerDescription) in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 328
   at App.CoreEngine.V5.DataAccess.DataContext.<>c__DisplayClass12.<GetCalculatedDataForCompare>b__f(Object _) in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 267
   at System.Threading.Tasks.Task.Execute()
   --- End of inner exception stack trace ---
   at System.Threading.Tasks.Task.WaitAll(Task[] tasks, Int32 millisecondsTimeout, CancellationToken cancellationToken)
   at CoreEngine.V5.DataAccess.DataContext.GetCalculatedDataForCompare() in C:\SourceCode\AppV1\Releases\Libraries\CoreEngine\CoreEngine.V5\DataAccess\DataContext.cs:line 276
   at System.Threading.Tasks.Task`1.InvokeFuture(Object futureAsObj)
   at System.Threading.Tasks.Task.Execute()

编辑 - 我只是仔细检查了发生这种情况的服务器是否打开了 dbcc 1222，我运行了 dbcc tracestatus 并得到:

TraceFlag   Status  Global  Session
1222    1   1   0
3605    1   1   0

并且在报告死锁的日志中没有任何内容

Answer 1

我的猜测是执行计划现在使用并行性，而之前它没有达到成本阈值。

在查询中尝试 MAXDOP 1

评论后编辑

您还需要跟踪标志 1204。

TF 1222 给出了死锁图，但是对于这个“通信缓冲区资源”死锁，可能不会涉及 2 个对象(我猜这里不是索引/表冲突)。参见 http://msdn.microsoft.com/en-us/library/ms178104.aspx

还有未记录的 TF 1205，它在错误日志中提供了更多信息