On Thu, 16 Apr 2020 at 10:33, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> what I know, pgbench cannot be used for testing spinlocks problems.
>
> Maybe you can see this issue when a) use higher number clients - hundreds, thousands. Decrease share memory, so there
willbe press on related spin lock.
There really aren't many spinlocks left that could be tickled by a
normal workload. I looked for a way to trigger spinlock contention
when I prototyped a patch to replace spinlocks with futexes. The only
one that I could figure out a way to make contended was the lock
protecting parallel btree scan. A highly parallel index only scan on a
fully cached index should create at least some spinlock contention.
Regards,
Ants Aasma