Yeah, you can't enable priority inheritance for mutexes in std of either C++ or Rust. Which is a show stopper for hard realtime (my dayjob).<p>And then you have mutexes internally inside some dependency still (e.g. grpc or what have you). What I would really like is the ability to change defaults for all mutexes created in the program, and have everyone use the same std mutexes.<p>By the way: rwlocks are often a bad idea, since you still get cache contention between readers on the counter for number of active readers. Unless the time you hold the lock for is really long (several milliseconds at least) it usually doesn't improve performance compared to mutexes. Consider alternatives like seqlocks, RCU, hazard pointers etc instead, depending on the specifics of your situation (there is no silver bullet when it comes to performance in concurrent primtitves).
> What I would really like is the ability to change defaults for all mutexes created in the program, and have everyone use the same std mutexes.<p>Assuming you're building the whole userspace at once with something like yocto... you can just patch pthread to change the default to PTHREAD_PRIO_INHERIT and silently ignore attempts to set it to PTHREAD_PRIO_NONE. It's a little evil though.<p>> By the way: rwlocks are often a bad idea<p>+1
That is a great terrible idea (I really have to think a bit more on that). Won't help for Rust, since the mutexes there use futex directly, so you would have to patch the standard library itself (and for futex it is more complex than just enabling a flag). Seems plausible that other libraries and language runtimes might do similar things.
i think both you guys have the same job as me lol