On 12/04/08 12:02, Bill Holler wrote: > Hi Tesla Dev, > > I have been experimenting not going into C3 or C2 when > the number of non-idle CPUs in the cpu-partion exceeds > a threshold. This is an attempt to regain the high load performance. > These numbers are on a 2-socket system. > > With C3 threshold = 40% active and C2 threshold = 60% active > the libmicro fork_1000 benchmark completes in 80/100 the time. > > With C3 threshold = 20% active and C2 threshold = 30% active > the libmicro fork_1000 benchmark completes in 50/100 the time. > These numbers are still about 80/100 slower than with c-states
These numbers are about 20/100 slower than with c-states disabled, or about 120/100 of the time with c-states disabled. Bill > totally disabled. > > > I am also going to experiment with cpu idle/wakeup rate. > I suspect this may be more important for performance than > the number of active cpus. > > Regards, > Bill >
