high CPU activity for interrupts

[John Baldwin]

On Saturday 19 November 2005 02:36 am, guru at sisis.de wrote:
> El día Friday, November 18, 2005 a las 01:40:42PM -0500, John Baldwin escribió:
> > > The high rate of interrupts are coming from cardbus somehow:
> > >
> > > $ vmstat -i
> > > interrupt                          total       rate
> > > irq0: clk                        1526386         99
> > > irq1: atkbd0                       19720          1
> > > irq4: sio0                             2          0
> > > irq6: fdc0                            10          0
> > > irq7:                                  3          0
> > > stray irq7                             3          0
> > > irq8: rtc                        1953511        127
> > > irq9: acpi0                         1102          0
> > > irq11: cbb1 pcm0++*            126785936       8304 <***********
> > > irq12: psm0                       116294          7
> > > irq14: ata0                        70657          4
> > > irq15: ata1                        33673          2
> > > Total                          130507297       8548
> >
> > The '++*' part means you have at least 4 other devices sharing that IRQ
> > line as well.  Can you do a "dmesg | grep 'irq 11'" and post the output?
>
> Thanks for the feedback and here it is;
>
> 	matthias
>
> fwohci0: <SiS 7007> mem 0xec000000-0xec000fff irq 11 at device 2.3 on pci0
> ohci0: <SiS 5571 USB controller> mem 0xec001000-0xec001fff irq 11 at device 3.0 on pci0
> ohci1: <SiS 5571 USB controller> mem 0xec002000-0xec002fff irq 11 at device 3.1 on pci0
> ohci2: <SiS 5571 USB controller> mem 0xec003000-0xec003fff irq 11 at device 3.2 on pci0
> sis0: <SiS 900> 10/100BaseTX> port 0x2000-0x20ff mem 0xec005000-0xec005fff irq 11 at
> device 4.0 on pci0
> pcm0: <SiS 7012> port 0x1800-0x187f,0x1c00-0x1cff irq 11 at device 2.7 on pci0
> pcm0: <SiS 7012> port 0x1800-0x187f,0x1c00-0x1cff irq 11 at device 2.7 on pci0
> drm0: <ATI Radeon Lf R250 Mobility 9000 M9> port 0xa000-0xa0ff mem 0xec100000-0xec10ffff,0xf0000000-0xf7ffffff irq 11 at
> device 0.0 on pci1

Ok, so the high number of interrupts can be coming from any one of these devices.
You can try building a custom kernel that doesn't include the various devices
(such as ohci, pcm, or radeon_drm) to see which devices are generating the large
number of interrupts.

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org