On Wed, May 05, 2004 at 09:14:38AM +0300, Micha Feigin wrote: > On Tue, May 04, 2004 at 09:39:48PM -0500, Erik Meitner wrote: > > I have an HP nx9005(model DK993A with an AMD XP-M 2400+) installed with > > Debian/testing and kernel 2.6.4. I am trying to track down a performance > > problem. > > When powered by AC the system performance is excellent. When powered by > > battery, the system is so sluggish that I prefer to just not use it. It > > is like it was running at 200 MHz. > > This occurs with frequency scaling turned OFF and the CPU running at > > 1788MHz. Is this the result of on-chip powersaving systems of the CPU, > > such as the delay time for the chip to go from low-power mode to full > > power? Is there any way of tweaking this behavior? > > > > Note the differences in the results of the bogomips benchmark below. > > > > Since /proc/cpuinfo shows the same value, AFAIK there is no frequency > change using cpufreq. Check /proc/acpi/processor/CPU0/throttling > though. You can throttle the cpu using acpi which doesn't cause > /etc/cpuinfo to show a different frequency. > > Could be that you have a frequency handling daemon that uses acpi > instead of cpufreq to throttle you laptop? Could also be your bios intervening. Another interesting test could be to compile cpufreq and set cpu frequency to the maximum manually on battery power, then run bogomips again. hth -- mattia :wq! -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
