Re: New FSM allocation policy

On Fri, 2008-08-29 at 18:55 +0300, Heikki Linnakangas wrote:
> Tom Lane wrote:
> > Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> >> One idea, we could scan the rest of the current page and use the first match.
> >
> >> Another, given the way your tree structure works you can also descend the tree
> >> with a "target" page. You can find the first page with enough free space after
> >> the target page if there are any. (Take left branch if it's > target and has
> >> enough free space else take right branch if there's enough free space else
> >> take left branch).
> >
> > I think the trick here is how to also preserve the property that
> > different backends tend to be inserting into different pages.
>
> Yep. If we just always look at the next page, there's the danger of
> having multiple backends compete for the same pages again.

Can the FSM hand out page ranges? That way we would be able to use the
next page logic without fear of competition.

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Simon Riggs www.2ndQuadrant.com
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