Hi all,
I am troubleshooting a locking issue have have taken a SQL Profiler trace to identify the blocked/blocking processes. Before taking the trace, read committed isolation using row versioning was enabled using ALTER Database [dbname] SET READ_COMMITTED_SNAPSHOT ON. However, the trace below is showing the READ COMMITTED still being used (see isolationlevel="read committed (2)") as shown in the trace below.
Two questions here:
1) Do you know why READ_COMMITTED_SNAPSHOT isn't being used?
2) Why is READ_COMMITTED_SNAPSHOT is not even listed as an output of sys.dm_exec_sessions?
Many thanks,
Louis
<blocked-process-report>
<blocked-process>
<process id="process5d3708" taskpriority="0" logused="0" waitresource="KEY: 5:72057595046002688 (938c9ead5edc)" waittime="83092" ownerId="6744110" transactionname="user_transaction"
lasttranstarted="2013-02-11T15:27:58.933" XDES="0x2137fd950" lockMode="U" schedulerid="3" kpid="3996" status="suspended" spid="55" sbid="0" ecid="0" priority="0"
trancount="2" lastbatchstarted="2013-02-11T15:27:58.950" lastbatchcompleted="2013-02-11T15:27:58.937" clientapp=".Net SqlClient Data Provider" hostname="DCT1-EFNT-WV01" hostpid="2664" loginname="efront"
isolationlevel="read committed (2)" xactid="6744110" currentdb="5" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
<executionStack>
<frame line="1" stmtstart="148" sqlhandle="0x020000004ee7e9256d2ee8fe99d21aae66986111bda25549"/>
<frame line="1" sqlhandle="0x000000000000000000000000000000000000000000000000"/>
</executionStack>
<inputbuf>
(@param0 int,@param1 datetime,@param2 varbinary(786),@param3 nvarchar(32))UPDATE ADMREGISTRY SET (removed) </inputbuf>
</process>
</blocked-process>
<blocking-process>
<process status="suspended" waitresource="KEY: 5:72057595046002688 (938c9ead5edc)" waittime="163879" spid="63" sbid="0" ecid="0" priority="0" trancount="2" lastbatchstarted="2013-02-11T15:26:38.167"
lastbatchcompleted="2013-02-11T15:26:38.147" clientapp=".Net SqlClient Data Provider" hostname="DCT1-EFNT-WV01" hostpid="2664" loginname="efront" isolationlevel="read committed (2)" xactid="6737833"
currentdb="5" lockTimeout="4294967295" clientoption1="671088672" clientoption2="128056">
<executionStack>
<frame line="1" stmtstart="150" sqlhandle="0x02000000f5a6a90b568b350edc53866a9ad355cf9d7978aa"/>
<frame line="1" sqlhandle="0x000000000000000000000000000000000000000000000000"/>
</executionStack>
<inputbuf>
(@param0 int,@param1 datetime,@param2 varbinary(2150),@param3 nvarchar(32))UPDATE ADMREGISTRY SET (removed) </inputbuf>
</process>
</blocking-process>
</blocked-process-report>