Bruce Momjian <pgman@candle.pha.pa.us> writes:
> but is there any significant performance benefit to doing that which would
> offset the compaction advantage?
Just as a side comment. Setting PCTFREE 0 PCTUSED 100 on tables that have no
updates on them has an astonishingly big effect on speed. So the penalty for
leaving some space free really is substantial.
I think the other poster is right. Oracle really needs pctfree because of the
way it handles updates. Postgres doesn't really need as much because it
doesn't try to squeeze the new tuple in the space the old one took up. If it
doesn't fit on the page the worst that happens is it has to store it on some
other page, whereas oracle has to do its strange row chaining thing.
--
greg
