[Edit 2014: there’s an additional bug in SQL Server 2012/2014 – see this post for details.]
Msg 831, Level 20, State 1, Line 1 Unable to deallocate a kept page.
More details are in KB article 919142, which was only recently made public.
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(This post first appeared on SQLperformance.com four years ago as part of a blog series, before that website was mothballed later in 2022 and the
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4 thoughts on “(Not a) CHECKDB error “Unable to deallocate a kept page””
Thanks Paul.
Hi Lads,
I meet this issues on SQL Server 2012 with AGs.
No fun at all.
Please find err logs below.
Should I contact to Microsoft directly ?
“
During undoing of a logged operation in database ‘databaseName’, an error occurred at log record ID (26946:8958:47). Typically, the specific failure is logged previously as an error in the Windows Event Log service. Restore the database or file from a backup, or repair the database.
Unable to deallocate a kept page.
SQL Server must shut down in order to recover a database (database ID 21). The database is either a user database that could not be shut down or a system database. Restart SQL Server. If the database fails to recover after another startup, repair or restore the database.
“
Yes – likely corruption that you’ll need to recover from.
I also met the same error as Jakub this weekend on a SQL 2012 SP1 (11.0.3349).
Any chance on “hoping” this bug was reintroduced by any chance?