Recently we had an unresponsive server due to the errorlog snippet shown.
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2012-09-17 09:58:24.97 Server Using 'dbghelp.dll' version '4.0.5'
2012-09-17 09:58:25.10 Server **Dump thread - spid = 0, EC = 0x00000000
2012-09-17 09:58:25.10 Server ***Stack Dump being sent to D:\Program Files\Microsoft SQL Server\MSSQL10.ABC123\MSSQL\LOG\SQLDump0002.txt
2012-09-17 09:58:25.10 Server * *******************************************************************************
2012-09-17 09:58:25.10 Server *
2012-09-17 09:58:25.10 Server * BEGIN STACK DUMP:
2012-09-17 09:58:25.10 Server * 09/17/12 09:58:25 spid 2408
2012-09-17 09:58:25.10 Server *
2012-09-17 09:58:25.10 Server * Deadlocked Schedulers
2012-09-17 09:58:25.10 Server *
2012-09-17 09:58:25.10 Server * *******************************************************************************
2012-09-17 09:58:25.10 Server * -------------------------------------------------------------------------------
2012-09-17 09:58:25.10 Server * Short Stack Dump
2012-09-17 09:58:25.22 Server Stack Signature for the dump is 0x000001B2
2012-09-17 09:58:35.78 Server External dump process return code 0x20000001.
External dump process returned no errors.
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Each query logging on ended up with the below msg in the errorlog.
2012-09-17 09:58:35.79 Server New queries assigned to process on Node 0 have not been picked up by a worker thread in the last 60 seconds. Blocking or long-running queries can contribute to this condition, and may degrade client response time. Use the "max worker threads" configuration option to increase number of allowable threads, or optimize current running queries. SQL Process Utilization: 0%. System Idle: 85%.
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We couldn't logon to the server using osql or mgmt studio or any other wayand we had no choice but to stop and restart sql services. (was it the right decision?)
But even stopping wasn't so easy, SQL Server was hung on "change pending" and then we'd to reboot the entire box and lateron everything came back normal.
Any advices?