Hello again. I know, that my problem is not so close related with the xenomai. But I think many of xenomai users with new intel CPUs have similar problem. I tried it it with two different main boards and none of the BIOS settings helped. (C-states: disabled, Speedstep: disabled, CPU idle: high performance, TurboBoost: disabled, ...). My theory is that the linux kernel overrides BIOS settings, but I don't know how to prove it. Any ideas that could help me?
Petr Cervenka ______________________________________________________________. > Od: "Petr Cervenka" <[email protected]> > Komu: "xenomai-help" <[email protected]> > Datum: 26.09.2011 09:02 > Předmět: Frequency downscaling of new intel CPU > >Hello. > >I recently tried newer computer and I suprusingly realized that it has bigger >load than the old one with our xenomai application. >The problem is in the frequency downscaling of the processor when the load in >under 100%. >Of course I have disabled CPU_FREQ, ACPI_PROCESSOR and INTEL_IDLE as suggested. >Later I tried also to disable CPU_IDLE, 7300_IDLE (intel chipset idle memory) >and all power efficiency settings in the BIOS, but without success. >The experienced behaviour is following: >when the process is waiting for an event, the processor lowers its frequency >and when the event happens it tries to restore (slowly) its nominal frequency. > >Do you have any advice or tip what to try, because I'm really desperate? > >Best regards > >Petr Cervenka > >configuration: >Xeon E3-1220 (Sandy Bridge) >linux-2.6.38.8 >xenomai-2.5.6 > _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
