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From: Tom Lane <tgl@sss.pgh.pa.us>
To: vignesh C <vignesh21@gmail.com>
cc: Andres Freund <andres@anarazel.de>,
        Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Printing backtrace of postgres processes
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Comments: In-reply-to vignesh C <vignesh21@gmail.com>
	message dated "Sat, 16 Jan 2021 23:04:52 +0530"
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vignesh C <vignesh21@gmail.com> writes:
> On Sat, Jan 16, 2021 at 1:40 AM Andres Freund <andres@anarazel.de> wrote:
>> Why is a full signal needed? Seems the procsignal infrastructure should
>> suffice?

> Most of the processes have access to ProcSignal, for these processes
> printing of callstack signal was handled by using ProcSignal. Pgstat
> process & syslogger process do not have access to ProcSignal,
> multiplexing with SIGUSR1 is not possible for these processes. So I
> handled the printing of callstack for pgstat process & syslogger using
> the SIGUSR2 signal.

I'd argue that backtraces for those processes aren't really essential,
and indeed that trying to make the syslogger report its own backtrace
is damn dangerous.

(Personally, I think this whole patch fails the safety-vs-usefulness
tradeoff, but I expect I'll get shouted down.)

			regards, tom lane