Re: Cancelling parallel query leads to segfault

On 1/27/18 22:45, Andres Freund wrote:
> I think the comment was bad, but the functionality pretty crucial. So I
> don't think
>     In AtAbort_Portals(), remove the code that marks an active portal as
>     failed.  As the comment there already predicted, this doesn't work if
>     the running command wants to keep running after transaction abort.  And
>     it's actually not necessary, because pquery.c is careful to run all
>     portal code in a PG_TRY block and explicitly runs MarkPortalFailed() if
>     there is an exception.  So the code in AtAbort_Portals() is never used
>     anyway.
> holds true, because FATAL errors do not follow the sigsetjmp chain.
> 
> I'm uncomfortable with the idea, but without further study, it does seem
> like you might be able to largely rescue the idea by checking
> proc_exit_in_progress or similar.

Here is a patch to implement that idea.  Do you have a way to test it
repeatedly, or do you just randomly cancel queries?

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
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