Re: [HACKERS] walsender & parallelism

On 24/04/17 01:43, Andres Freund wrote:
> 
>> BTW while looking at the code, I don't understand why we call
>> latch_sigusr1_handler after calling SetLatch(MyLatch), shouldn't just
>> the SetLatch be enough (they both end up calling sendSelfPipeByte()
>> eventually)?
> 
> Historic raisins - there didn't use to be a SetLatch in
> procsignal_sigusr1_handler. That changed when I whacked around catchup &
> notify to be based on latches ([1] and following).
> 
> [1] https://git.postgresql.org/gitweb/?p=postgresql.git;a=commit;h=59f71a0d0b56b2df48db4bf1738aece5551f7a47
> 

Okay, but why call both SetLatch and latch_sigusr1_handler? What does
that buy us?

--  Petr Jelinek                  http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training &
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