Re: Adding REPACK [concurrently]

Hello, Antonin!

On Mon, Nov 3, 2025 at 8:56 AM Antonin Houska <ah(at)cybertec(dot)at> wrote:
> I'll fix all the problems in the next version. Thanks!

A few more moments I mentioned:

> switch ((vis = HeapTupleSatisfiesVacuum(tuple, OldestXmin, buf)))
vis is unused, also to double braces.

> LockBuffer(buf, BUFFER_LOCK_UNLOCK);
> continue;
> }

> /*
> * In the concurrent case, we have a copy of the tuple, so we
> * don't worry whether the source tuple will be deleted / updated
> * after we release the lock.
> */
> LockBuffer(buf, BUFFER_LOCK_UNLOCK);
>}

I think locking and comments are a little bit confusing here.
I think we may use single LockBuffer(buf, BUFFER_LOCK_UNLOCK); before
`if (isdead)` as it was before.
Also, I am not sure "we have a copy" is the correct point here, I
think motivation is mostly the same as in
heapam_index_build_range_scan.

Also, I think it is a good idea to add tests for index-based and
sort-based repack.

Also, for sort-based I think we need to also call
repack_decode_concurrent_changes during insertion phase

> is_system_catalog && !concurrent
2 places, always true, feels strange.

Best regards,
Mikhail.