On 05/06/2024 23:55, Robert Haas wrote:
On Wed, Jun 5, 2024 at 4:32 PM Tristan Partin <tris...@partin.io> wrote:
Not entirely sure how I feel about the approach you've taken, but here
is a patch that Heikki and I put together for extension compatibility.
It's not a build time solution, but a runtime solution. Instead of
PG_MODULE_MAGIC, extensions would use PG_MAGIC_MODULE_REENTRANT. There
is a GUC called `multithreaded` which controls the variable
IsMultithreaded. We operated under the assumption that being able to
toggle multithreading and multi-processing without recompiling has
value.
That's interesting, because I thought Heikki was against having a
runtime toggle.
I'm very much in favor of a runtime toggle. To be precise, a
PGC_POSTMASTER setting. We'll get a lot more testing if you can easily
turn it on/off, and so far I haven't seen anything that would require it
to be a compile time option.
I don't think PG_MODULE_MAGIC_REENTRANT is a good syntax. It all looks
great as long as we only ever need the PG_MODULE_MAGIC line to signal
one bit of information, but as soon as you get to two bits it's pretty
questionable, and anything more than two bits is insane. If we want to
do something with the PG_MODULE_MAGIC line, I think it should involve
options-passing of some form rather than just having an alternate
macro name.
+1, that would be nicer.
--
Heikki Linnakangas
Neon (https://neon.tech)
