On Thu, 16 Apr 2020 at 10:33, Pavel Stehule <pavel.steh...@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 will be 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
