Re: Performance monitor signal handler

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Alfred Perlstein <bright@wintelcom.net>
Cc: Philip Warner <pjw@rhyme.com.au>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2001-03-13T15:03:18Z
Lists: pgsql-hackers
> > I think Tom has previously stated that there are technical reasons not to
> > do IO in signal handlers, and I have philosophical problems with
> > performance monitors that ask 50 backends to do file IO. I really do think
> > shared memory is TWTG.
> 
> I wasn't really suggesting any of those courses of action, all I
> suggested was using rename(2) to give a seperate appilcation a
> consistant snapshot of the stats.
> 
> Actually, what makes the most sense (although it may be a performance
> killer) is to have the backends update a system table that the external
> app can query.

Yes, it seems storing info in shared memory and having a system table to
access it is the way to go.

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