The default Angstrom build has a service that starts 10 minutes after boot and switches the governor to on-demand.
I disabled it on my system and have been happy with the results.I recommend digging into the files to understand what is happening, but I used this command: systemctl disable cpu-ondemand.timer Wim. On Sat, Sep 28, 2013 at 8:26 AM, Vaibhav Bedia <[email protected]>wrote: > On Sat, Sep 28, 2013 at 8:52 AM, Harry May <[email protected]> wrote: > > I spent hours finding a bug in my GPIO kernel driver (blocking the > system) > > until I found the reason: > > > > While the system has to process a lot of data (interrupts), i.e. > streaming > > of music, video, or handling signals from a GPIO. > > the kernel hangs showing an I2C controller timeout in the journal. > > > > This always happens when the CPU frequency is atomatically switched by > the > > cpu governor. > > > > I am using this commands to disable frequency switching: > > > > cpufreq-set -c 0 -g performance > > cpufreq-set -d 1GHz > > cpufreq-set -u 1GHz > > > > to check if it worked: cpufreq-info > > > > this must print the line: > > current policy: frequency should be within 1000 MHz and 1000 MHz. > > > > If somebody knows a better way to disable thew cpu governor, please tell > us. > > > > Is there any plan to solve the conflict between the cpu governor and the > I2C > > causing I2C contoller timeouts ? > > > > If you know beforehand that the system needs to start operating at 1GHz you > could switch over to the userspace governor and then set the frequency. > Using the userspace governor ensures that the frequency doesn't change > automatically. This could in theory impact the average power consumption > but > can be used as a stopgap solution till you find out why the timeouts > are happening > in the first place. > > Regards, > Vaibhav > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to the Google Groups > "BeagleBoard" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
