Re: PG 14 release notes, first draft

On Mon, May 10, 2021 at 07:54:24AM -0700, Peter Geoghegan wrote:
> On Mon, May 10, 2021 at 4:44 AM Matthias van de Meent
>  wrote:
> > I noticed that the improvement in bloat control in the HeapAM that I
> > know of (3c3b8a4b, 0ff8bbde) weren't documented here. Although each
> > can be considered minor, they together can decrease the bloating
> > behaviour of certain workloads significantly (and limit the total
> > damage), and in my opinion this should be mentioned.
> >
> > 3c3b8a4b: Returns space claimed for the line pointer array back to the
> > page's empty space, so that it can also be used for tuple data.
> >
> > 0ff8bbde: Allows large tuples to be inserted on pages which have only
> > a small amount of data, regardless of fillfactor.
> 
> +1 on mentioning both things.

OK, you are confirming what Matthias suggested.  I added these two
items, which both seem to apply only to heap pages, not index pages:

---------------------------------------------------------------------------

	
	
	
	
	Deallocate space reserved by trailing unused heap line pointers
	(Matthias van de Meent, Peter Geoghegan)
	
	
	
---------------------------------------------------------------------------

	
	
	
	
	Allow wide tuples to be always added to almost-empty heap pages (John Naylor,
	Floris van Nee)
	
	
	
	Previously tuples whose insertion would have exceeded the page's fill
	factor were instead added to new pages.
	
	

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  EDB                                      https://enterprisedb.com

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