Re: Moving sp_thread_pause, sp_thread_sleep to Core

From: Gavin Lambert (boost_at_[hidden])
Date: 2023-06-02 00:24:46

On 2/06/2023 11:43, Peter Dimov wrote:
> Gavin Lambert wrote:
>> FWIW though, atomic_* on shared_ptr is entirely banned in my codebase
>> precisely because of its spinlock implementation.
> 
> Which part is wrong?

Caused massive performance issues in my codebase.  Not really a fault of 
your implementation per se (other than it's a spinlock at all), just a 
consequence of priority inversion plus too many collisions in the 
spinlock pool.  Probably not something that would be a problem for most 
apps; I just have some special quirks.

It's not only spinlocks (though they're worse than regular locks); any 
locks at all have to justify themselves pretty hard (I use a lot of 
lock-free techniques and structures, and non-blocking "locks" like 
strands and workqueues).

I have a custom lock that behaves better in my environment, so it's nice 
when things that do require a lock either leave the app to handle that 
externally or allow it to be configured via template.