Krunal Bauskar <krunalbauskar@gmail.com> writes:
> So given all the permutations and combinations, I think we could approach
> the problem as follows:
> * Enable use of CAS as it is known to have optimal performance (vs TAS)
The results I posted at [1] seem to contradict this for Apple's new
machines.
In general, I'm pretty skeptical of *all* the results posted so far on
this thread, because everybody seems to be testing exactly one machine.
If there's one thing that it's safe to assume about ARM, it's that
there are a lot of different implementations; and this area seems very
very likely to differ across implementations.
I don't have a big problem with catering for a few different spinlock
implementations on ARM ... but it's sure unclear how we could decide
which one to use.
regards, tom lane
[1] https://www.postgresql.org/message-id/741389.1606530957@sss.pgh.pa.us