Re: Yet another fast GiST build

[Andrey M. Borodin]

> 21 сент. 2020 г., в 13:45, Heikki Linnakangas <hlinn...@iki.fi> написал(а):
> 
> On 21/09/2020 11:08, Heikki Linnakangas wrote:
>> I think they need to, so that they can stamp the page with the LSN of
>> the WAL record. But GiST build is special in that regard, because it
>> stamps all pages with GistBuildLSN.
> 
> Actually, don't we have a problem with that, even before this patch? Even 
> though we set the LSN to the magic GistBuildLSN value when we build the 
> index, WAL replay will write the LSN of the record instead. That would mess 
> with the LSN-NSN interlock. After WAL replay (or in a streaming replica), a 
> scan on the GiST index might traverse right-links unnecessarily.

I think we don't set rightlinks during index build.

Best regards, Andrey Borodin.