Submission + - Why Linux Sucks (batteries)
An anonymous reader writes: Last July Dave Jones entertained the audience at the Ottawa Linux Symposium with a talk titled
Why Userspace Sucks in
which he described many hyperactive applications performing needless busywork.
Now Arjan van de Ven has come up with a tool named powertop that points the finger directly at which applications and device drivers are draining your laptop battery by waking the CPU from idle hundreds of times per second.
Low power states on modern processors can save significant amounts of power, but only if the cpu stays in the low power state for long enough to amortize the energy used to get into and out of the low power state. Powertop reports the total number of times the cpu is woken each second, the average time spent in each C-state, and the top ten offenders who wake the CPU from its slumbers.
Keith Packard reported that by using this tool to fix or eliminate the worst offenders he increased his battery life from four hours to almost seven!
Now Arjan van de Ven has come up with a tool named powertop that points the finger directly at which applications and device drivers are draining your laptop battery by waking the CPU from idle hundreds of times per second.
Low power states on modern processors can save significant amounts of power, but only if the cpu stays in the low power state for long enough to amortize the energy used to get into and out of the low power state. Powertop reports the total number of times the cpu is woken each second, the average time spent in each C-state, and the top ten offenders who wake the CPU from its slumbers.
Keith Packard reported that by using this tool to fix or eliminate the worst offenders he increased his battery life from four hours to almost seven!
