Re: WIP patch for parallel pg_dump

Dimitri Fontaine <dimitri@2ndquadrant.fr>

From: Dimitri Fontaine <dimitri@2ndQuadrant.fr>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: Joachim Wieland <joe@mcknight.de>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2010-12-02T12:00:21Z
Lists: pgsql-hackers
Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> I don't see the point of the sort-by-relpages code. The order the objects
> are dumped should be irrelevant, as long as you obey the restrictions
> dictated by dependencies. Or is it only needed for the multiple-target-dirs
> feature? Frankly I don't see the point of that, so it would be good to cull
> it out at least in this first stage.

From the talk at CHAR(10), and provided memory serves, it's an
optimisation so that you're doing largest file in a process and all the
little file in other processes. In lots of case the total pg_dump
duration is then reduced to about the time to dump the biggest files.

Regards,
-- 
Dimitri Fontaine
http://2ndQuadrant.fr     PostgreSQL : Expertise, Formation et Support