Re: Thoughts on maintaining 7.3

Bruce Momjian wrote:
> > The reason I'm waffling about whether the problem is completely fixed or
> > not is that the existing code will only remove-and-recycle completely
> > empty btree pages.  As long as you have one key left on a page it will
> > stay there.  So you could end up with ridiculously low percentage-filled
> > situations.  This could be fixed by collapsing together adjacent
> > more-than-half-empty pages, but we ran into a lot of problems trying to
> > do that in a concurrent fashion.  So I'm waiting to find out if real
> > usage patterns have a significant issue with this or not.
> 
> If we have an exclusive lock during VACUUM FULL, should we just collapse
> the pages rather than REINDEX?  I realize we might have lots of expired
> index tuples because VACUUM FULL creates new ones as part of
> reorganizing the heap.

Never mind --- I remember now that we are going to use VACUUM for a few
updates, and VACUUM FULL for big updates.

--  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,
Pennsylvania19073