Re: remove flatfiles.c

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Greg Stark <gsstark(at)mit(dot)edu>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, Pg Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: remove flatfiles.c
Date: 2009-09-02 02:55:14
Message-ID: 603c8f070909011955t5046cbffx272584cb005fb12f@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On Tue, Sep 1, 2009 at 7:42 PM, Tom Lane<tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Greg Stark <gsstark(at)mit(dot)edu> writes:
>> On Wed, Sep 2, 2009 at 12:01 AM, Alvaro
>> Herrera<alvherre(at)commandprompt(dot)com> wrote:
>>>> The use cases where VACUUM FULL wins currently are where storing two
>>>> copies of the table and its indexes concurrently just isn't practical.
>>>
>>> Yeah, but then do you really need to use VACUUM FULL?  If that's really
>>> a problem then there ain't that many dead tuples around.
>
>> That's what I want to believe. But picture if you have, say a
>> 1-terabyte table which is 50% dead tuples and you don't have a spare
>> 1-terabytes to rewrite the whole table.
>
> But trying to VACUUM FULL that table is going to be horridly painful
> too, and you'll still have bloated indexes afterwards.  You might as
> well just live with the 50% waste, especially since if you did a
> full-table update once you'll probably do it again sometime.
>
> I'm having a hard time believing that VACUUM FULL really has any
> interesting use-case anymore.

What if your large table doesn't have an index? Then there's no way to cluster.

I'm a bit skeptical about partitioning as a solution, too. The
planner is just not clever enough with partitioned tables, yet.

...Robert

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2009-09-02 02:56:04 Re: remove flatfiles.c
Previous Message Tom Lane 2009-09-02 02:45:43 Re: make installcheck is broken in HEAD on mingw