两个进程在同一资源上死锁

Question

我不是死锁专家，但我所看到的对我来说并不合理。似乎两个不同的进程在同一个对象上死锁。一个进程难道不会等待资源被释放并继续它的生命吗？通常有死锁，涉及2个资源，这就是为什么我感到困惑。

死锁：

<deadlock-list>
 <deadlock victim="process53f288">
  <process-list>
   <process id="process53f288" taskpriority="0" logused="264" waitresource="KEY: 7:72057594065977344 (651c594e0a33)" waittime="4406" ownerId="293044707" transactionname="user_transaction" lasttranstarted="2013-10-03T15:41:21.040" XDES="0x80cd53c0" lockMode="X" schedulerid="1" kpid="14284" status="suspended" spid="92" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2013-10-03T15:41:21.560" lastbatchcompleted="2013-10-03T15:41:21.553" clientapp=".Net SqlClient Data Provider" hostname="MCCMTLMCS001" hostpid="2952" loginname="asapdb" isolationlevel="read committed (2)" xactid="293044707" currentdb="7" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
    <executionStack>
     <frame procname="adhoc" line="1" stmtstart="34" sqlhandle="0x0200000065487b054151f9a8d40f9f90d40cba7ff11e6228">
UPDATE InnoPickCaseList SET DestinationSpiral = @p0 WHERE Sequence = @p1     </frame>
     <frame procname="unknown" line="1" sqlhandle="0x000000000000000000000000000000000000000000000000">
unknown     </frame>
    </executionStack>
    <inputbuf>
(@p0 int,@p1 int)UPDATE InnoPickCaseList SET DestinationSpiral = @p0 WHERE Sequence = @p1    </inputbuf>
   </process>
   <process id="process7ed948" taskpriority="0" logused="4556" waitresource="KEY: 7:72057594065977344 (62b5bdcd3e80)" waittime="4403" ownerId="293044717" transactionname="user_transaction" lasttranstarted="2013-10-03T15:41:21.050" XDES="0x1298df950" lockMode="X" schedulerid="4" kpid="7344" status="suspended" spid="94" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2013-10-03T15:41:21.560" lastbatchcompleted="2013-10-03T15:41:21.557" clientapp=".Net SqlClient Data Provider" hostname="MCCMTLMCS001" hostpid="2952" loginname="asapdb" isolationlevel="read committed (2)" xactid="293044717" currentdb="7" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
    <executionStack>
     <frame procname="adhoc" line="1" stmtstart="34" sqlhandle="0x0200000065487b054151f9a8d40f9f90d40cba7ff11e6228">
UPDATE InnoPickCaseList SET DestinationSpiral = @p0 WHERE Sequence = @p1     </frame>
     <frame procname="unknown" line="1" sqlhandle="0x000000000000000000000000000000000000000000000000">
unknown     </frame>
    </executionStack>
    <inputbuf>
(@p0 int,@p1 int)UPDATE InnoPickCaseList SET DestinationSpiral = @p0 WHERE Sequence = @p1    </inputbuf>
   </process>
  </process-list>
  <resource-list>
   <keylock hobtid="72057594065977344" dbid="7" objectname="ExactaDB.dbo.InnoPickCaseList" indexname="PK_InnoPickCaseList" id="locka7110b00" mode="X" associatedObjectId="72057594065977344">
    <owner-list>
     <owner id="process7ed948" mode="X"/>
    </owner-list>
    <waiter-list>
     <waiter id="process53f288" mode="X" requestType="wait"/>
    </waiter-list>
   </keylock>
   <keylock hobtid="72057594065977344" dbid="7" objectname="ExactaDB.dbo.InnoPickCaseList" indexname="PK_InnoPickCaseList" id="lockbb807a80" mode="X" associatedObjectId="72057594065977344">
    <owner-list>
     <owner id="process53f288" mode="X"/>
    </owner-list>
    <waiter-list>
     <waiter id="process7ed948" mode="X" requestType="wait"/>
    </waiter-list>
   </keylock>
  </resource-list>
 </deadlock>
</deadlock-list>

图形

其他细节

• InnoPickCaseList.Sequence是表上的主键，它有一个聚簇索引
• 表通常包含大约10k条记录

我认为问题正在发生，因为特定应用程序正在进行更新。本质上，有两个不同的线程可以在事务中更新同一组数据（InnoPickCaseList.Sequence数字的范围），但它可能以不同的顺序进行更新。此时我做了一个更改，就是在两个不同的线程中以相同的方式对数据进行排序，以便更新以相同的顺序进行。

Answer 1

有两种不同的资源。一个是散列a7110b00的密钥，另一个是散列bb807a80的密钥。是真的，他们属于同一个对象ExactaDB.dbo.InnoPickCaseList.PK_InnoPickCaseList，但它们是不同的。

1. 您有Sequence的索引吗？
2. Sequence列的选择性是多少（多少个不同的值）？
3. InnoPickCaseList有多大？