Re: Some thoughts about i/o priorities and throttling vacuum

Greg Stark wrote:

> Christopher Browne <cbbrowne@libertyrms.info> writes:
> 
>>VACUUM is like putting an extra few transport trucks onto the highway.
>>It may only go from one highway junction to the next, and be fairly
>>brief, if traffic is moving well.  But if traffic is heavy, it adds to
>>the congestion.  (And that's as far as the analogy can go; I can't
>>imagine a way of drawing the GUC parameter into this...)
> 
> Ooh strained metaphors. This game is always fun.
> 
> So I think of it the other way around. A busy database is like downtown
> traffic with everyone going every which way for short trips. Running vacuum is
> like having a few trucks driving through your city streets for through
> traffic. 
> 
> Having a parameter to slow down the through traffic is like, uh, having
> express lanes for local traffic. er, yeah, that's the ticket. Except who ever
> heard of having express lanes for local traffic. Hm.

All I know is that Jan Wieck would have each car filled to the brim
with spikes....

Mike Mascari
mascarm@mascari.com