Re: Buglist

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Jan Wieck <JanWieck@Yahoo.com>
Cc: Andrew Sullivan <andrew@libertyrms.info>, pgsql-general@postgresql.org
Date: 2003-08-20T21:58:32Z
Lists: pgsql-hackers, pgsql-general
Jan Wieck <JanWieck@Yahoo.com> writes:
> What about a little hint to the buffer management that if it has to 
> evict another buffer to physically read this one (meaning the buffer 
> pool was full already) then it will not put this buffer at the top of 
> the LRU chain but rather at it's end? This way a vacuum on a large table 
> will not cause a complete cache eviction.

I think what we really need is a way to schedule VACUUM's I/O at a lower
priority than normal I/Os.  Wouldn't be very portable :-( ... but if the
OS offers a facility for requesting this, it'd be worth experimenting
with.

			regards, tom lane