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

On Mon, Feb 26, 2024 at 08:50:28PM -0500, Melanie Plageman wrote:
> 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.

Thomas posted a new version of the Streaming Read API [1], so here is a
rebased v5. This should make it easier to review as it can be applied on
top of master.

- Melanie

[1] https://www.postgresql.org/message-id/CA%2BhUKGJtLyxcAEvLhVUhgD4fMQkOu3PDaj8Qb9SR_UsmzgsBpQ%40mail.gmail.com