It looks like there are futexes down there in the hairball that is glibc. AFAICT either they or atomic test-and-set are used to implement pthread mutexes, rather than an OS call (but I just glanced at the code, so don't take my word for it).

If thread-switching performance is really critical, and pthreads are too slow, would some form of cooperative threading work?

In reply to Re^9: OT: Locking and syncing mechanisms available on *nix. by educated_foo
in thread OT: Locking and syncing mechanisms available on *nix. by BrowserUk

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