From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nigel Cunningham Subject: Re: 2.6.33 & 2.6.34-rc6: Huge number of Load Balancing tick wakeups. Date: Mon, 10 May 2010 09:48:18 +1000 Message-ID: <4BE749C2.50300@crca.org.au> References: <4BE4F5DF.70903@crca.org.au> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Len Brown Cc: LKML , Linux Power Management List List-Id: linux-pm@vger.kernel.org Hi again. On 09/05/10 05:16, Len Brown wrote: > What do you see if vmware is not present? > What do you see if you boot single user mode, > how about with maxcpusx=1? Repeated the tests, just booting into X (xfce) - except for the init S test. No programs were started and wifi was turned off. 1) No vmware (etc) Cn Avg residency C0 (cpu running) ( 3.7%) polling 0.0ms ( 0.0%) C1 mwait 0.0ms ( 0.0%) C2 mwait 0.1ms ( 0.3%) C4 mwait 5.4ms (96.0%) P-states (frequencies) Turbo Mode 1.4% 2.21 Ghz 0.0% 1.60 Ghz 0.0% 1200 Mhz 0.0% 800 Mhz 98.6% Wakeups-from-idle per second : 202.7 interval: 15.0s no ACPI power usage estimate available Top causes for wakeups: 56.1% (128.5) [kernel scheduler] Load balancing tick 13.1% ( 30.1) [extra timer interrupt] 6.9% ( 15.9) [ata_piix] 2) Above + maxcpus=1 Cn Avg residency C0 (cpu running) ( 4.0%) polling 0.0ms ( 0.0%) C1 mwait 0.0ms ( 0.0%) C2 mwait 0.4ms ( 0.2%) C4 mwait 16.0ms (95.9%) P-states (frequencies) Turbo Mode 6.0% 2.21 Ghz 0.0% 1.60 Ghz 0.0% 1200 Mhz 0.0% 800 Mhz 94.0% Wakeups-from-idle per second : 64.5 interval: 15.0s no ACPI power usage estimate available Top causes for wakeups: 39.6% ( 46.3) [kernel scheduler] Load balancing tick 12.3% ( 14.3) [ata_piix] (No idea why you need a load balancing tick with one core!) 3) Init S, without maxcpus=1 Cn Avg residency C0 (cpu running) ( 0.0%) polling 0.0ms ( 0.0%) C1 mwait 0.0ms ( 0.0%) C2 mwait 0.1ms ( 0.0%) C4 mwait 48.9ms (100.0%) P-states (frequencies) Turbo Mode 0.0% 2.21 Ghz 0.0% 1.60 Ghz 0.0% 1200 Mhz 0.0% 800 Mhz 100.0% Wakeups-from-idle per second : 21.4 interval: 15.0s no ACPI power usage estimate available Top causes for wakeups: 33.5% ( 10.3) [kernel core] hrtimer_start (tick_sched_timer) 16.1% ( 4.9) [kernel core] cursor_timer_handler (cursor_timer_handler) 15.9% ( 4.9) [kernel scheduler] Load balancing tick 12.8% ( 3.9) [kernel core] usb_hcd_poll_rh_status (rh_timer_func) 9.3% ( 2.9) [ahci] I also tried the patch Dominik provided, and it didn't seem to make a difference: P-states (frequencies) Turbo Mode 3.7% 2.21 Ghz 0.0% 1.60 Ghz 0.0% 1200 Mhz 0.6% 800 Mhz 95.7% Wakeups-from-idle per second : 236.7 interval: 15.0s no ACPI power usage estimate available Top causes for wakeups: 55.4% (119.7) [kernel scheduler] Load balancing tick 9.7% ( 20.9) skype 7.7% ( 16.5) [ata_piix] Regards, Nigel