Re: Experimental patch for inter-page delay in VACUUM - Mailing list pgsql-hackers

From Hannu Krosing
Subject Re: Experimental patch for inter-page delay in VACUUM
Date
Msg-id 1067813484.3357.20.camel@fuji.krosing.net
Whole thread Raw
In response to Re: Experimental patch for inter-page delay in VACUUM  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Tom Lane kirjutas P, 02.11.2003 kell 20:00:
> Jan Wieck <JanWieck@Yahoo.com> writes:
> > I am currently looking at implementing ARC as a replacement strategy. I 
> > don't have anything that works yet, so I can't really tell what the 
> > result would be and it might turn out that we want both features.
> 
> It's likely that we would.  As someone (you?) already pointed out,
> VACUUM has bad side-effects both in terms of cache flushing and in
> terms of sheer I/O load.  Those effects require different fixes AFAICS.
> 
> One thing that bothers me here is that I don't see how adjusting our
> own buffer replacement strategy is going to do much of anything when
> we cannot control the kernel's buffer replacement strategy.  

At least for OpenSource/Free OS'es it would probably be possible to
persuade kernel developers to give the needed control to userspace apps.

So the "take over all RAM" is not the only option ;)

> To get any
> real traction we'd have to go back to the "take over most of RAM for
> shared buffers" approach, which we already know to have a bunch of
> severe disadvantages.
> 
>             regards, tom lane
> 
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster


pgsql-hackers by date:

Previous
From: Tom Lane
Date:
Subject: Re: Avoiding SIGPIPE (was Re: OSDL DBT-2 w/ PostgreSQL
Next
From: Fabrizio Mazzoni
Date:
Subject: pgsql crosstab function