Tom,
> The bigger problem here is that the SMP locking bottlenecks we are
> currently seeing are *hardware* issues (AFAICT anyway). The only way
> that futexes can offer a performance win is if they have a smarter way
> of executing the basic atomic-test-and-set sequence than we do;
> and if so, we could read their code and adopt that method without having
> to buy into any large reorganization of our code.
Well, initial results from Gavin/Neil's patch seem to indicate that, while
futexes do not cure the CSStorm bug, they do lessen its effects in terms of
real performance loss.
--
--Josh
Josh Berkus
Aglio Database Solutions
San Francisco