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sakuraime avatar image
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sakuraime asked sakuraime commented

Always-on REDO log blocked

Any chances the redo log blocked is waiting for an X lock on a page? ( i usually see waiting for SCH-M only)

sql-server-general
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Cathyji-msft avatar image
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Cathyji-msft answered sakuraime commented

Hi @sakuraime,

Did you meet the block issue? When the redo thread is blocked, an extended event called sqlserver.lock_redo_blocked is generated. Additionally, you can query the DMV sys.dm_exec_request on the secondary replica to find out which session is blocking the REDO thread, and then you can take corrective action.


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yes . that's what I check from lock_redo_blocked... the requesting waiting for a lock is an X lock on a Page. ...Just want to know how to make it possible?

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Hi anyone has the idea ?

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Hi @sakuraime,

Could you share us the result from lock_redo_blocked? Did you use sys.dm_exec_request on the secondary replica to find out which session is blocking the REDO thread

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I don't have real time records of sys.dm_exec_request , and I can't share too much about the xevent .
what I can see is a X mode lock , and also waiting on a page .

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