Red Hat Bugzilla – Bug 587816
Regression kernel 2.6.33.2-41 -> 2.6.33.2-57 / i915 60 interrupts/s
Last modified: 2010-12-01 12:29:06 EST
Description of problem: Since kernel 2.6.33.2-57 powertop shows about 60 i915 interrupts per second on an idle machine. Kernel 2.6.33.2-41 was fine. ================== kernel 2.6.33.2-57 ================== PowerTOP 1.11 (C) 2007, 2008 Intel Corporation Collecting data for 10 seconds Cn Avg residency C0 (cpu running) ( 2.2%) C0 0.0ms ( 0.0%) C1 halt 0.0ms ( 0.0%) C2 0.2ms ( 0.1%) C3 7.8ms (97.7%) P-states (frequencies) 2.01 Ghz 2.0% 2.00 Ghz 0.0% 1.60 Ghz 0.4% 1200 Mhz 0.2% 800 Mhz 97.3% Wakeups-from-idle per second : 129.3 interval: 10.0s no ACPI power usage estimate available Top causes for wakeups: 32.0% ( 64.9) <kernel core> : hrtimer_start_range_ns (tick_sched_timer) 29.4% ( 59.7) <interrupt> : i915 12.0% ( 24.4) <kernel IPI> : Rescheduling interrupts 5.4% ( 11.0) <interrupt> : uhci_hcd:usb6, ath 4.3% ( 8.7) <kernel core> : hrtimer_start (tick_sched_timer) 3.6% ( 7.3) <interrupt> : ahci 2.5% ( 5.0) <interrupt> : ata_piix 2.1% ( 4.2) <interrupt> : acpi 2.0% ( 4.0) <kernel core> : __mod_timer (rh_timer_func) ================== kernel 2.6.33.2-41 ================== PowerTOP 1.11 (C) 2007, 2008 Intel Corporation Sammle Daten für 10 Sekunden Cn Verweildauer C0 (Prozessor läuft) ( 2,2%) C0 0,0ms ( 0,0%) C1 halt 0,0ms ( 0,0%) C2 0,2ms ( 0,1%) C3 14,1ms (97,7%) P-States (Frequenzen) 2,01 GHz 4,7% 2,00 GHz 0,0% 1,60 GHz 1,0% 1200 MHz 0,0% 800 MHz 94,3% Aufwachen pro Sekunde : 73,0 Intervall: 10,0s Keine ACPI Stromverbrauch-Schätzung verfügbar Häufigste Ursachen für das Aufwachen: 46,2% ( 72,0) <Kernel Kern> : hrtimer_start_range_ns (tick_sched_timer) 15,4% ( 24,0) <Kernel IPI> : Rescheduling interrupts 10,3% ( 16,0) <interrupt> : uhci_hcd:usb6, ath 8,3% ( 12,9) <Kernel Kern> : hrtimer_start (tick_sched_timer) 3,2% ( 5,0) <interrupt> : ata_piix
The same problem in kernel 2.6.33.3-72.fc13.x86_64
I'm experiencing the same behavior, AFAIK it's due to a problem in the intel graphics driver, see: http://www.lesswatts.org/projects/powertop/known.php#intelgfx
@Attilio: I thought this bug was fixed a long time ago. The same problem in kernel 2.6.33.4-95.fc13.x86_64.
The same problem in kernel 2.6.33.5-112.fc13.x86_64. # lspci -vvv 00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03) Subsystem: Acer Incorporated [ALI] Device 011f Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 0 Region 0: Memory at fc100000 (64-bit, non-prefetchable) [size=1M] Capabilities: [d0] Power Management version 3 Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-) Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME- Bridge: PM- B3+ I've attached the output of # inteltool -a I can provide more infos on request. The other two boxes I own (945 chipset) don't snow 60 interrupts/s.
Created attachment 418622 [details] inteltool -a
Technical note added. If any revisions are required, please edit the "Technical Notes" field accordingly. All revisions will be proofread by the Engineering Content Services team. New Contents: The problem disappeared in Fedora 14.