Bug 16052
| Summary: | one core is always at 100% while the others at less than 5% | ||
|---|---|---|---|
| Product: | Platform Specific/Hardware | Reporter: | Andrew (atswartz) |
| Component: | x86-64 | Assignee: | platform_x86_64 (platform_x86_64) |
| Status: | CLOSED CODE_FIX | ||
| Severity: | normal | CC: | akpm, kay, maciej.rutecki, rjw |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 2.6.34-git9 | Subsystem: | |
| Regression: | Yes | Bisected commit-id: | |
| Bug Depends on: | |||
| Bug Blocks: | 16055 | ||
| Attachments: | sysrq-trigger | ||
|
Description
Andrew
2010-05-26 13:16:25 UTC
How are you observing this CPU consumption? Is there a process running on the CPU? If so, which? Does /proc/interrupts indicate that there's a lot of interrupt activity? Do sysrq-p or sysrq-t enable you to see what's running on that CPU? I'll mark this as a regression, thanks. (In reply to comment #1) > How are you observing this CPU consumption? > GNOME system monitor initially alerted me to the problem. > Is there a process running on the CPU? If so, which? > PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 666 root 16 -4 6532 1044 408 R 100 0.1 5:17.84 udevd > Does /proc/interrupts indicate that there's a lot of interrupt activity? > looks normal to me. $ cat /proc/interrupts CPU0 CPU1 CPU2 CPU3 0: 126 0 0 1 IO-APIC-edge timer 1: 0 0 0 53 IO-APIC-edge i8042 7: 1 0 0 0 IO-APIC-edge 8: 0 0 1 140 IO-APIC-edge rtc0 9: 0 0 0 1 IO-APIC-fasteoi acpi 16: 0 0 6 6461 IO-APIC-fasteoi ohci_hcd:usb2, pata_marvell, hda_intel 17: 0 0 0 2 IO-APIC-fasteoi ohci_hcd:usb3, ohci_hcd:usb5 18: 0 0 0 2 IO-APIC-fasteoi ohci_hcd:usb4, ohci_hcd:usb6 19: 0 0 0 2 IO-APIC-fasteoi ehci_hcd:usb1, pata_marvell 22: 0 0 17 8758 IO-APIC-fasteoi ahci, ohci1394 44: 0 0 9 2243 PCI-MSI-edge radeon 45: 0 0 5 1212 PCI-MSI-edge sky2@pci:0000:03:00.0 46: 0 0 0 262 PCI-MSI-edge hda_intel NMI: 0 0 0 0 Non-maskable interrupts LOC: 55478 124463 58209 90241 Local timer interrupts SPU: 0 0 0 0 Spurious interrupts PMI: 0 0 0 0 Performance monitoring interrupts PND: 0 0 0 0 Performance pending work RES: 45147 866 32578 12309 Rescheduling interrupts CAL: 38 63 66 37 Function call interrupts TLB: 1046 113 1295 1663 TLB shootdowns THR: 0 0 0 0 Threshold APIC interrupts MCE: 0 0 0 0 Machine check exceptions MCP: 1 1 1 1 Machine check polls ERR: 1 MIS: 0 > Do sysrq-p or sysrq-t enable you to see what's running on that CPU? > <Alt><SysRq><t> nothing echo t > /proc/sysrq-trigger nothing <Alt><SysRq><p> [root@asus ~]# 2010 May 26 11:10:42 asus [ 571.044780] Stack: 2010 May 26 11:10:42 asus [ 571.044811] Call Trace: 2010 May 26 11:10:42 asus [ 571.044832] Code: 71 00 85 db 75 3c 65 48 8b 04 25 48 b5 00 00 83 a0 3c e0 ff ff fb 0f ae f0 48 8b 80 38 e0 ff ff a8 08 75 7c e8 d5 3a 09 00 fb f4 <65> 48 8b 04 25 48 b5 00 00 83 88 3c e0 ff ff 04 48 83 c4 08 5b > I'll mark this as a regression, thanks. (In reply to comment #2) > (In reply to comment #1) > > Do sysrq-p or sysrq-t enable you to see what's running on that CPU? > > > <Alt><SysRq><t> nothing > echo t > /proc/sysrq-trigger nothing > <Alt><SysRq><p> > [root@asus ~]# 2010 May 26 11:10:42 asus [ 571.044780] Stack: > 2010 May 26 11:10:42 asus [ 571.044811] Call Trace: > 2010 May 26 11:10:42 asus [ 571.044832] Code: 71 00 85 db 75 3c 65 48 8b 04 > 25 > 48 b5 00 00 83 a0 3c e0 ff ff fb 0f ae f0 48 8b 80 38 e0 ff ff a8 08 75 7c e8 > d5 3a 09 00 fb f4 <65> 48 8b 04 25 48 b5 00 00 83 88 3c e0 ff ff 04 48 83 c4 > 08 > 5b Please run `dmesg -n 1' then retry these. Created attachment 26551 [details]
sysrq-trigger
Here is the output of <Alt><SysRq><T>
ah, OK, sorry, I didn't look at comment #2 closely enough - udevd is spinning. Your sysrq-t trace shows the udevd stack trace. Let me go and ask Kay and Greg.. Probably this, a borked FIONREAD kernel bug: http://lkml.org/lkml/2010/5/23/100 this problem is fixed for me in 2.6.34-git16 (20100530) & 2.6.35-rc1 Thanks. |