It would be interesting to see SPECpower numbers comparing a base run with one where you have offlined a subset of the processors. That's the first existing knob we could expose as a way to save power.
I've been running my dual-core laptop with one of the cores down, and powertop and gnome-power-statistics do show a difference. Rafael Bill Holler wrote: > We currently do not allow the user to select a power/performance profile. > This seems like something we eventually require for tunablity. > > The initial OpenSolaris could not introduce any performance regressions > over a wide range of benchmarks. There is a huge opportunity for > tuning for power if we are not constrained by 100% performance. > I definitely saw during evaluation power improvements from c-state > governor changes such as Aubrey's proposal. There are a number of > thread scheduling improvements as well I would like to get back to. ;-) > Having power/perf profiles or "knobs" would really make it easier > to introduce better algorithms which work really well in specific > situations with different power, performance, and response time > requirements. > > Regards, > Bill > > > > On 05/22/09 16:17, Bill Holler wrote: >> Hi Aubrey, >> >> Time based sample periods were initially investigated, but they >> performed poorly with "ping pong" type workloads such as >> producer consumer etc. The problem was it took too long to >> recognize a load change when the CPU had very short idle >> and load periods. The current idle-rate based sampling shows >> very little to no regression on benchmarks such as libmicro. >> >> How does the proposed change look in libmicro? >> >> We may need to use a hybrid governor which looks at both >> idle rate and a fixed sample period. >> >> Thank you, >> Bill >> _______________________________________________ >> tesla-dev mailing list >> tesla-dev at opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/tesla-dev > > _______________________________________________ > tesla-dev mailing list > tesla-dev at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/tesla-dev
