Re: [HACKERS] possible self-deadlock window after bad ProcessStartupPacket - Mailing list pgsql-hackers

From Tom Lane
Subject Re: [HACKERS] possible self-deadlock window after bad ProcessStartupPacket
Date
Msg-id 23058.1532029775@sss.pgh.pa.us
Whole thread Raw
In response to Re: [HACKERS] possible self-deadlock window after badProcessStartupPacket  (Andres Freund <andres@anarazel.de>)
Responses Re: [HACKERS] possible self-deadlock window after badProcessStartupPacket  (Nico Williams <nico@cryptonector.com>)
Re: [HACKERS] possible self-deadlock window after badProcessStartupPacket  (Andres Freund <andres@anarazel.de>)
List pgsql-hackers
Andres Freund <andres@anarazel.de> writes:
> On 2018-07-19 11:57:25 +0300, Heikki Linnakangas wrote:
>> The regular backend's quickdie() function is more tricky. It should also
>> call _exit(2) rather than exit(2). But it also tries to ereport a WARNING,
>> and that is quite useful.

There's already an on_exit_reset in there; why do we need more than that?

> Is that actually true? Clients like libpq create the same error message
> (which has its own issues, because it'll sometimes mis-interpret
> things). The message doesn't actually have useful content, no?

Yes, it does: it lets users tell the difference between exit due to a
SIGQUIT and a crash of their own backend.

Admittedly, if we crash trying to send the message, then we're not
better off.  But since that happens only very rarely, I do not think
it's a reasonable tradeoff to never send it at all.

            regards, tom lane


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