Sorry to bring this one back alive, but i'm actually finding this problem still exists on Ubuntu 10.04 running the 2.6.32-24-generic-pae kernel.
I'm running a W510 laptop (quad-core) with HT disabled, and to try and save power (especially given the kernel interrupt problem atm) I tried disabling 1/2/3 of the 4 cores. My logic behind it was that the core would physically be powered down (no interrupts at all), and would use little to no power. In doing this, powertop informed me my idle power usage rose from 17W to 33W, not good on a laptop! I can reproduce this each time by disabling a single or multiple cores. Also, if I re-enable them all, power usage decreases. Given how this kernel interface is designed to allow for a CPU to be hotplugged in a live server, it seems strange in my mind that it is still supplying power to it. -- disabling a CPU increases laptop power consumption https://bugs.launchpad.net/bugs/54601 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
