Re: [PoC] Improve dead tuple storage for lazy vacuum

On Wed, Feb 22, 2023 at 3:29 PM Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com>
wrote:
>
> On Wed, Feb 22, 2023 at 4:35 PM John Naylor
> <john(dot)naylor(at)enterprisedb(dot)com> wrote:
> >
> > I don't think any vacuum calls in regression tests would stress any of
this code very much, so it's not worth carrying the old way forward. I was
thinking of only doing this as a short-time sanity check for testing a
real-world workload.
>
> I guess that It would also be helpful at least until the GA release.
> People will be able to test them easily on their workloads or their
> custom test scenarios.

That doesn't seem useful to me. If we've done enough testing to reassure us
the new way always gives the same answer, the old way is not needed at
commit time. If there is any doubt it will always give the same answer,
then the whole patchset won't be committed.

TPC-C was just an example. It should have testing comparing the old and new
methods. If you have already done that to some degree, that might be
enough. After performance tests, I'll also try some vacuums that use the
comparison patch.

--
John Naylor
EDB: http://www.enterprisedb.com