Re: Memory leaks in record_out and record_send
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: pgsql-hackers@postgresql.org
Date: 2012-11-13T20:21:09Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes: > On Tue, Nov 13, 2012 at 12:18 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote: >> I wonder though if we ought to think about running output functions in >> a short-lived memory context instead of the executor's main context. >> We've considered that before, I think, and it's always been the path >> of least resistance to fix the output functions instead --- but there >> will always be another leak I'm afraid. > Such is the lot of people who code in C. I worry that the number of > memory contexts we're kicking around already is imposing a significant > distributed overhead on the system that is hard to measure but > nevertheless real, and that this will add to it. Yeah, perhaps. I'd like to think that a MemoryContextReset is cheaper than a bunch of retail pfree's, but it's hard to prove anything without actually coding and testing it --- and on modern machines, effects like cache locality could swamp pure instruction-count gains anyway. Anyway, I committed the narrow fix for the moment. regards, tom lane