Re: BitmapHeapScan streaming read user and prelim refactoring - Mailing list pgsql-hackers

On Fri, Feb 16, 2024 at 12:35:59PM -0500, Melanie Plageman wrote:
> In the attached v3, I've reordered the commits, updated some errant
> comments, and improved the commit messages.
> 
> I've also made some updates to the TIDBitmap API that seem like a
> clarity improvement to the API in general. These also reduce the diff
> for GIN when separating the TBMIterateResult from the
> TBM[Shared]Iterator. And these TIDBitmap API changes are now all in
> their own commits (previously those were in the same commit as adding
> the BitmapHeapScan streaming read user).
> 
> The three outstanding issues I see in the patch set are:
> 1) the lossy and exact page counters issue described in my previous
> email

I've resolved this. I added a new patch to the set which starts counting
even pages with no visible tuples toward lossy and exact pages. After an
off-list conversation with Andres, it seems that this omission in master
may not have been intentional.

Once we have only two types of pages to differentiate between (lossy and
exact [no longer have to care about "has no visible tuples"]), it is
easy enough to pass a "lossy" boolean paramater to
table_scan_bitmap_next_block(). I've done this in the attached v4.

- Melanie