Re: Add 64-bit XIDs into PostgreSQL 15

Hi hackers,

> In this part, I suppose you've found a definite bug. Thanks! There are a couple
> of ways how it could be fixed:
>
> 1. If we enforce checkpoint at replica promotion then we force full-page writes after each page modification afterward.
>
> 2. Maybe it's worth using BufferDesc bit to mark the page as converted to 64xid but not yet written to disk? For example, one of four bits from BUF_USAGECOUNT.
> BM_MAX_USAGE_COUNT = 5 so it will be enough 3 bits to store it. This will change in-memory page representation but will not need WAL-logging which is impossible on a replica.
>
> What do you think about it?

I'm having difficulties merging and/or testing
v8-0002-Add-64bit-xid.patch since I'm not 100% sure which commit this
patch was targeting. Could you please submit a rebased patch and/or
share your development branch on GitHub?

I agree with Bruce it would be great to deliver this in PG15. Please
let me know if you believe it's unrealistic for any reason so I will
focus on testing and reviewing other patches.

For now, I'm changing the status of the patch to "Waiting on Author".

--
Best regards,
Aleksander Alekseev