I installed Ubuntu 14.10 on a Lenovo Thinkpad, which is a All-In_One Desktop without any batteries.
System is working fine, up to 2 problems:
Shortly after logon, the desktop is shown and even a terminal autostarted. Then, suddenly, the display resolution is again reset (i.e. screen goes dark), and when it comes back I see the message "Battery critically low". This is merely an annoyance, from that point on, the system continues to work. But it makes me wary that the system doesn't know exactly my computer.
Probably related, I have always 4 kidle_inject processes slowing down each logical CPU by 20 to 50%, even if the system is more than 80% idle according to top. I already tried to disable intel_pstate, but it has no effect. What an idiotic situation! Dear LINUX/Ubuntu devs, don't you think that when I want to save power, I buy a smaller CPU. Now, the situation is such, when I do a full rebuild of my project (I do Java development) on the machine, it simply takes twice as long, just for sake of "power saving". And working in eclipse is barely impossible, unless I quit chrome and any other applications. So please, tell me:
How can I disable any and all stuff that redcues my CPU performance? Specifically kidle_inject?
EDIT: found out that there is a device driver named
intel_powerclamp that injects the idle time, and how to disable it.
What could be the reason my desktop is treated as a battery-powered device, and how to suppress it?