Re: [sqlsmith] Unpinning error in parallel worker - Mailing list pgsql-hackers

From Jonathan Rudenberg
Subject Re: [sqlsmith] Unpinning error in parallel worker
Date
Msg-id 1523998351.1231357.1341528496.28EBAF7F@webmail.messagingengine.com
Whole thread Raw
In response to Re: [sqlsmith] Unpinning error in parallel worker  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: [sqlsmith] Unpinning error in parallel worker
List pgsql-hackers
On Wed, Mar 29, 2017, at 10:50, Robert Haas wrote:
> On Wed, Mar 29, 2017 at 1:31 AM, Thomas Munro
> <thomas.munro@enterprisedb.com> wrote:
> > I considered whether the error message could be improved but it
> > matches the message for an existing similar case (where you try to
> > attach to an unknown handle).
> 
> Ugh, OK.  I committed this, but I think this whole file needs a visit
> from the message style police.

I ran into an issue that matches the symptoms of this bug on a production cluster running 10.3 (Ubuntu
10.3-1.pgdg16.04+1)twice in the past week.
 

Hundreds of queries stuck with a wait_event of DynamicSharedMemoryControlLock and pg_terminate_backend did not
terminatethe queries.
 

In the log:

> FATAL:  cannot unpin a segment that is not pinned

I don't have a backtrace yet, but I will provide them if/when the issue happens again.

Jonathan


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