死锁图和解释，避免的解决方案

Question

死锁图和解释，避免的解决方案

我支持基于供应商的应用程序，它充满了块和死锁。死锁主要涉及两个或三个进程，但是我昨天注意到，它涉及 9 个 SPID。

有人可以帮助我理解这个死锁图和如何避免这种情况的解决方案。

<deadlock><victim-list><victimProcess id="process2ff017c28"/><victimProcess id="process2f1538108"/><victimProcess id="process2f618d088"/><victimProcess id="process2f6d828c8"/><victimProcess id="process2f6d83848"/><victimProcess id="process2da9b5468"/><victimProcess id="process2efac7468"/><victimProcess id="process2efac7848"/></victim-list><process-list><process id="process2ff017c28" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4412" ownerId="284194209" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:29:07.323" XDES="0x2a785f800" lockMode="IX" schedulerid="1" kpid="9052" status="suspended" spid="63" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.733" lastbatchcompleted="2019-04-08T15:30:58.733" lastattention="1900-01-01T00:00:00.733" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284194209" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2f1538108" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4411" ownerId="284107628" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:24:11.843" XDES="0xdacf54e0" lockMode="IX" schedulerid="1" kpid="7272" status="suspended" spid="73" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.737" lastbatchcompleted="2019-04-08T15:30:58.727" lastattention="1900-01-01T00:00:00.727" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284107628" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2f618d088" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4620" ownerId="284193487" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:28:59.513" XDES="0x20df303b0" lockMode="IX" schedulerid="2" kpid="2088" status="suspended" spid="79" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.527" lastbatchcompleted="2019-04-08T15:30:58.527" lastattention="1900-01-01T00:00:00.527" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284193487" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2f6d828c8" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4302" ownerId="284194269" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:29:07.743" XDES="0x25090c6d0" lockMode="IX" schedulerid="3" kpid="3140" status="suspended" spid="105" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.843" lastbatchcompleted="2019-04-08T15:30:58.843" lastattention="1900-01-01T00:00:00.843" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284194269" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2f6d83848" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4319" ownerId="284178892" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:26:38.450" XDES="0xb83c63b0" lockMode="IX" schedulerid="3" kpid="7372" status="suspended" spid="81" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.827" lastbatchcompleted="2019-04-08T15:30:58.827" lastattention="1900-01-01T00:00:00.827" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284178892" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2da9b5468" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4300" ownerId="284174799" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:25:26.760" XDES="0x20d4683b0" lockMode="IX" schedulerid="3" kpid="5664" status="suspended" spid="97" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.847" lastbatchcompleted="2019-04-08T15:30:58.847" lastattention="1900-01-01T00:00:00.847" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284174799" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2efac7468" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4394" ownerId="284192570" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:28:49.180" XDES="0x184e789f0" lockMode="IX" schedulerid="4" kpid="5348" status="suspended" spid="98" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.753" lastbatchcompleted="2019-04-08T15:30:58.753" lastattention="1900-01-01T00:00:00.753" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284192570" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2efac7848" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4409" ownerId="284178168" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:26:23.063" XDES="0x2420aab80" lockMode="IX" schedulerid="4" kpid="4572" status="suspended" spid="68" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.740" lastbatchcompleted="2019-04-08T15:30:58.737" lastattention="1900-01-01T00:00:00.737" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284178168" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process><process id="process2efac7c28" taskpriority="0" logused="0" waitresource="OBJECT: 11:1142295129:0 " waittime="4413" ownerId="284177493" transactionname="implicit_transaction" lasttranstarted="2019-04-08T15:26:12.160" XDES="0xab9103b0" lockMode="IX" schedulerid="4" kpid="2448" status="suspended" spid="52" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2019-04-08T15:30:58.733" lastbatchcompleted="2019-04-08T15:30:58.733" lastattention="1900-01-01T00:00:00.733" clientapp="jTDS" hostname="APPNAME" hostpid="123" loginname="IRB_APP_USER" isolationlevel="repeatable read (3)" xactid="284177493" currentdb="11" currentdbname="Database_Name" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128058"><executionStack><frame procname="adhoc" line="1" stmtstart="46" stmtend="180" sqlhandle="0x02000000b6b6e728e6bf289c908196a1f4e56b8892a5eab10000000000000000000000000000000000000000">
unknown    </frame></executionStack><inputbuf>
(@P0 bigint,@P1 bigint)update Table_Name set STATUS_ID= @P0  where id= @P1    </inputbuf></process></process-list><resource-list><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2f6d828c8" mode="S"/><owner id="process2da9b5468" mode="S"/><owner id="process2f6d828c8" mode="IX" requestType="convert"/><owner id="process2da9b5468" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2ff017c28" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d828c8" mode="S"/><owner id="process2da9b5468" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2f6d828c8" mode="IX" requestType="convert"/><owner id="process2da9b5468" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2f1538108" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d828c8" mode="S"/><owner id="process2da9b5468" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2f6d828c8" mode="IX" requestType="convert"/><owner id="process2da9b5468" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2f618d088" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f618d088" mode="S"/><owner id="process2da9b5468" mode="S"/><owner id="process2f618d088" mode="IX" requestType="convert"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2da9b5468" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2f6d828c8" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f618d088" mode="S"/><owner id="process2da9b5468" mode="S"/><owner id="process2f618d088" mode="IX" requestType="convert"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2da9b5468" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2f6d83848" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d83848" mode="S"/><owner id="process2efac7848" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2efac7848" mode="IX" requestType="convert"/><owner id="process2f6d83848" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2da9b5468" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d83848" mode="S"/><owner id="process2efac7848" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2efac7848" mode="IX" requestType="convert"/><owner id="process2f6d83848" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2efac7468" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d83848" mode="S"/><owner id="process2efac7468" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2efac7468" mode="IX" requestType="convert"/><owner id="process2f6d83848" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2efac7848" mode="IX" requestType="convert"/></waiter-list></objectlock><objectlock lockPartition="0" objid="1142295129" subresource="FULL" dbid="11" objectname="Database_Name.Schema_Name.Table_Name" id="lock2149d8800" mode="S" associatedObjectId="1142295129"><owner-list><owner id="process2ff017c28" mode="S"/><owner id="process2f6d83848" mode="S"/><owner id="process2efac7468" mode="S"/><owner id="process2ff017c28" mode="IX" requestType="convert"/><owner id="process2efac7468" mode="IX" requestType="convert"/><owner id="process2f6d83848" mode="IX" requestType="convert"/></owner-list><waiter-list><waiter id="process2efac7c28" mode="IX" requestType="convert"/></waiter-list></objectlock></resource-list></deadlock>

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隔离级别在数据库级别设置为 Read Committed Snapshot。

当我在哨兵一号计划资源管理器中打开这个死锁图时，它很可怕。

Answer 1

Aar*_*and 12

这显然是隔离级别、锁升级和许多会话的糟糕组合，每个会话在同一事务中发出多个查询。

如果您展开服务员/所有者列表，您会看到他们都在尝试访问相同的资源（大概是整个表）：

还有一种不那么可怕的方式是优化布局并使用强制定向：

如果您重播死锁，您将看到所有这些不同的会话在相对较长的时间内（5 分钟以上，这很疯狂，尽管动画确实隐藏了这一点）保持其事务处于打开状态，并且间歇性地发出多个查询。您需要大幅减少在这些事务中花费的时间（或完全摆脱它们），将针对不同参数值的多个查询合并为单个时间点查询，构建更好的索引以便升级不会发生，停止强制重复读取，创建聚集索引（如果我正确读取资源描述符，那是一个堆！？），或以上所有。

Answer 2

Ran*_*gen 10

您的默认隔离级别可能是 Read Committed Snapshot，但您的应用程序设置的隔离级别 = repeatable read (3)

对于死锁中的所有更新语句，这些是隔离级别：

isolationlevel="repeatable read (3)"

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这是在连接级别使用以下命令完成的：

SET TRANSACTION ISOLATION LEVEL REPEATABLE READ

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可重复读 SQL Server 隔离级别可防止脏读和不可重复读。它是通过在事务中每个语句读取的所有数据上放置共享锁来实现的，并且所有锁都被持有直到事务完成。因此，其他事务无法修改当前事务已读取的数据。但是，它并不会阻止其他事务将新行插入到当前事务中已选择的表中关于可重复读的部分解释here

事务相互阻塞，在可重复读隔离级别下锁升级会导致阻塞，并且作为阻塞的副产品，死锁。

等待资源的阻塞查询：

waitresource="OBJECT: 11:1142295129:0 "

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几个进程在这个整个对象上有共享锁：

<owner id="process2ff017c28" mode="S"/><owner id="process2f6d828c8" mode="S"/><owner id="process2da9b5468" mode="S"/>

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并且这些相同的进程在这些对象上有几个意图排他锁

 <owner id="process2f6d828c8" mode="IX" requestType="convert"/>

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而 requestType="convert"解释说明进程正在尝试将共享锁转换为 IX 锁。

正如@David Browne - 微软解释的那样：

在可重复读取中，与挂起的 IX 锁冲突的对象级 S 锁可能已在事务中的较早查询中获得。

这意味着一个合理的解释是所有这些事务都试图将它们自己的共享锁（例如，由于先前的选择）转换为排他锁（更新语句）。由于处于可重复读隔离级别，他们不想放弃他们的锁，从而导致死锁。

你能做什么

您应该联系应用程序团队/供应商，看看这是否是必要的邪恶，因为阻塞将更加普遍。

在检查隔离级别之后，您应该研究通过添加索引来加速事务内部的查询。

Answer 3

Jos*_*ell 10

XML 图中的另一个问题是您似乎打开了“implicit_transactions”：

交易名称=“隐含交易”

如果应用程序没有明确关闭事务，这也可能导致阻塞。这可以在连接级别设置，也可以通过SET IMPLICIT TRANSACTIONS ON显式调用来设置。

看看这些时间：

您有从 15:25:26 开始的事务，这些事务仍在 15:30:58 运行。五分钟对于持有锁来说通常太长了 - 这是阻塞和死锁的秘诀。这似乎可能是一个意外的开放的挥之不去的交易。

如果您对应用程序的连接字符串有任何控制权，请确认他们没有打开此设置。此外，请仔细检查这不是通过服务器级别设置的sp_configure 'user options（有关更多详细信息，请参见此处）。

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