Re: Question about DB VACUUM

Sorry to be such a pain on this, but we are running postgres on a system
where we are using a 512MB compact flash as our physical disk media, so
disk space usage is of utmost importance.

Chris

-----Original Message-----
From: pgsql-admin-owner(at)postgresql(dot)org
[mailto:pgsql-admin-owner(at)postgresql(dot)org] On Behalf Of Christopher
Browne
Sent: Wednesday, October 08, 2003 6:22 AM
To: pgsql-admin(at)postgresql(dot)org
Subject: Re: [ADMIN] Question about DB VACUUM

In the last exciting episode, cjwhite(at)cisco(dot)com ("Chris White
(cjwhite)") wrote:
> BTW, the connection I shutdown, had not read, written or deleted any
> large objects. It had read and written to other tables. This is
> causing me concern as I am using a thread pool to provide access to
> the data in the large object table, and this seems to imply I have to
> close each connection after reading/writing or deleting a large object

> in order for me to truly reclaim unused space when I issue my periodic

> vacuum command.

Yup, that sounds like a more-than-vaguely familiar story...

The implication may not be _precisely_ correct, but the difference
between what you're expecting and reality seems to be difficult to get
at.

I would expect that if you fired a (perhaps trivial) transaction through
each of the connections once in a while, that would "clear things up"
too. How to accomplish that may be the challenge...
--
wm(X,Y):-write(X),write('@'),write(Y). wm('cbbrowne','ntlug.org').
http://www.ntlug.org/~cbbrowne/postgresql.html
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necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead." -- RFC 1925

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