Re: (auto)vacuum truncate exclusive lock

Alvaro Herrera <alvherre@2ndquadrant.com>

From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Kevin Grittner <kgrittn@ymail.com>, Jeff Janes <jeff.janes@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2013-04-12T18:08:26Z
Lists: pgsql-hackers
Tom Lane escribió:

> Are you saying you intend to revert that whole concept?  That'd be
> okay with me, I think.  Otherwise we need some thought about how to
> inform the stats collector what's really happening.

Maybe what we need is to consider table truncation as a separate
activity from vacuuming.  Then autovacuum could invoke it without having
to do a full-blown vacuum.  For this to work, I guess we would like to
separately store the status of the back-scan in pgstat somehow (I think
a boolean flag suffices: "were we able to truncate all pages that
appeared to be empty?")

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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