Re: BUG #17949: Adding an index introduces serialisation anomalies.

Hi Thomas,


thank you for the fixes. I've looked up the patches in pg's git repo, 
and they got me wondering: where is the repo with pg tests? I'd be 
really uneasy to make changes to concurrency-related code without a 
decent testsuite to verify them.


Best regards,

Artem.


On 04/07/2023 01:02, Thomas Munro wrote:
> On Wed, Jun 28, 2023 at 3:18 PM Thomas Munro <thomas.munro@gmail.com> wrote:
>> I'll push these in a couple of days if there are no further comments.
> Done.
>
> Thanks Artem, Dmitry and Heikki.
>
> I wonder how we might be more systematic about this.  There are some
> general principles that were not respected here, but I'm not sure if
> they're even written down let alone defended with code.  Something to
> think about.
>
> It's not great to add a new use of BufferGetBlockNumber() (in terms of
> false sharing just to get a value that we must have had moment earlier
> in order to pin the buffer), but we do that all the time.  That seems
> like a micro-optimisation worth looking into in some systematic way
> across all AMs.