Re: Yet another fast GiST build - Mailing list pgsql-hackers

From Andrey M. Borodin
Subject Re: Yet another fast GiST build
Date
Msg-id 47CD54A6-EE59-433A-96E2-6F4E5973CEF4@yandex-team.ru
Whole thread Raw
In response to Re: Yet another fast GiST build  (Heikki Linnakangas <hlinnaka@iki.fi>)
Responses Re: Yet another fast GiST build  (Heikki Linnakangas <hlinnaka@iki.fi>)
List pgsql-hackers

> 21 сент. 2020 г., в 13:45, Heikki Linnakangas <hlinnaka@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
GistBuildLSNvalue when we build the index, WAL replay will write the LSN of the record instead. That would mess with
theLSN-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.


pgsql-hackers by date:

Previous
From: Christoph Berg
Date:
Subject: Re: Binaries on s390x arch
Next
From: Julien Rouhaud
Date:
Subject: Re: Is deduplicate_items ever used in nbtree?