Re: [HACKERS] posmaster failed under high load - Mailing list pgsql-hackers

From Tom Lane
Subject Re: [HACKERS] posmaster failed under high load
Date
Msg-id 8811.926000406@sss.pgh.pa.us
Whole thread Raw
In response to Re: [HACKERS] posmaster failed under high load  (Bruce Momjian <maillist@candle.pha.pa.us>)
Responses Re: [HACKERS] posmaster failed under high load  (Oleg Broytmann <phd@sun.med.ru>)
List pgsql-hackers
Bruce Momjian <maillist@candle.pha.pa.us> writes:
>> The only way to get around this is to do an execv(), at which point the
>> kernel will recopy argv[0].

> We used to do execv(), but stopped doing it for performance reasons.

It's clearly not worth re-introducing the exec call just to make ps
status display work (especially since it's only failing when the backend
is swapped out).  However, I wonder whether there is another answer.

Something that's been on my to-do list since the ps-status-display code
got added is to import "sendmail"'s ps-status-display module lock, stock,
and barrel.  Sendmail's code is kinda ugly, but it's been wrung out and
works on a wide variety of Unixes.  The code we have doesn't ... (it's
never worked on my HPUX box, for instance, whereas sendmail does).

I have no idea at the moment whether sendmail knows how to change the
task_struct on Linux; but it might.
        regards, tom lane


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