Re: profiling connection overhead

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>, HeikkiLinnakangas <heikki.linnakangas@enterprisedb.com>
Date: 2010-11-24T21:25:45Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Nov 24, 2010, at 4:05 PM, Andres Freund <andres@anarazel.de> wrote:
>> Yes, but only once. Also scrubbing a page is faster than copying it... (and 
>> there were patches floating around to do that in advance, not sure if they got 
>> integrated into mainline linux)

> I'm not following - can you elaborate?

I think Andres is saying that bss space isn't optimized during a fork
operation: it'll be propagated to the child as copy-on-write pages.
Dunno if that's true or not, but if it is, it'd be a good reason to
avoid the scheme you're suggesting.

			regards, tom lane