Re: prevent immature WAL streaming

On 2021-Sep-08, Kyotaro Horiguchi wrote:

> Thanks! As my understanding the new record add the ability to
> cross-check between a teard-off contrecord and the new record inserted
> after the teard-off record. I didn't test the version by myself but
> the previous version implemented the essential machinery and that
> won't change fundamentally by the new record.
>
> So I think the current patch deserves to see the algorithm actually
> works against the problem.

Here's a version with the new record type. It passes check-world, and
it seems to work correctly to prevent overwrite of the tail end of a
segment containing a broken record. This is very much WIP still;
comments are missing and I haven't tried to implement any sort of
verification that the record being aborted is the right one.

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
"XML!" Exclaimed C++. "What are you doing here? You're not a programming
language."
"Tell that to the people who use me," said XML.
https://burningbird.net/the-parable-of-the-languages/