Re: [mail] Re: 7.4 Wishlist

Bruce Momjian <pgman@candle.pha.pa.us>

From: Bruce Momjian <pgman@candle.pha.pa.us>
To: Greg Copeland <greg@CopelandConsulting.Net>
Cc: Al Sutton <al@alsutton.com>, "Stephen L." <jleelim@hotmail.com>, PostgresSQL Hackers Mailing List <pgsql-hackers@postgresql.org>, "Joshua D. Drake" <jd@commandprompt.com>
Date: 2002-12-10T19:38:41Z
Lists: pgsql-hackers, pgsql-general
Greg Copeland wrote:
> On Tue, 2002-12-10 at 11:25, Al Sutton wrote:
> > Would it be possible to make compression an optional thing, with the default
> > being off?
> > 
> 
> I'm not sure.  You'd have to ask Command Prompt (Mammoth) or wait to see
> what appears.  What I originally had envisioned was a per database and
> user permission model which would better control use.  Since compression
> can be rather costly for some use cases, I also envisioned it being
> negotiated where only the user/database combo with permission would be
> able to turn it on.  I do recall that compression negotiation is part of
> the Mammoth implementation but I don't know if it's a simple capability
> negotiation or part of a larger scheme.

I haven't heard anything about them contributing it.  Doesn't mean it
will not happen, just that I haven't heard it.

I am not excited about per-db/user compression because of the added
complexity of setting it up, and even set up, I can see cases where some
queries would want it, and others not.  I can see using GUC to control
this.  If you enable it and the client doesn't support it, it is a
no-op.  We have per-db and per-user settings, so GUC would allow such
control if you wish.

Ideally, it would be a tri-valued parameter, that is ON, OFF, or AUTO,
meaning it would determine if there was value in the compression and do
it only when it would help.

-- 
  Bruce Momjian                        |  http://candle.pha.pa.us
  pgman@candle.pha.pa.us               |  (610) 359-1001
  +  If your life is a hard drive,     |  13 Roberts Road
  +  Christ can be your backup.        |  Newtown Square, Pennsylvania 19073