Ingo Molnar wrote: > > * Nathan Lynch <[EMAIL PROTECTED]> wrote: > > So it would be nice to have the scheduler slightly prefer primary > > threads on POWER6 machines. These patches, which allow the > > architecture to override the scheduler's CPU "power" calculation, are > > one possible approach, but I'm open to others. Please note: these > > seemed to have the desired effect on 2.6.25-rc kernels (2-3% > > improvement in a kernbench-like make -j <nr_cores>), but I'm not > > seeing this improvement with 2.6.26-rc kernels for some reason I am > > still trying to track down. > > ok, i guess that discrepancy has to be tracked down before we can think > about these patches - but the principle is OK.
Great. I'll keep trying to figure out what's going on there. > One problem is that the whole cpu-power balancing code in sched.c is a > bit ... unclear and under-documented. So any change to this area should > begin at documenting the basics: what do the units mean exactly, how are > they used in balancing and what is the desired effect. > > I'd not be surprised if there were a few buglets in this area, SMT is > not at the forefront of testing at the moment. There's nothing > spectacularly broken in it (i have a HT machine myself), but the > concepts have bitrotten a bit. Patches - even if they just add comments > - are welcome :-) Okay, I'll have a look. Thanks Ingo. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
