Hi Ranjan, May be misconfigured interrupt SMP affinity.See if this link helps: http://www.alexandersandler.net/smp-affinity-and-proper-interrupt-handling-in-linux
Regards Mayur On Thu, Dec 11, 2008 at 1:22 PM, Ranjan Sinha <[EMAIL PROTECTED]> wrote: > Hi, > > I had asked this question about a year or two back, and unfortunately > i still haven't quite understood this. A sense of deja vu. I have a > dual core machine running Ubuntu 8.10 with the kernel supplied by the > distribution. Here are the details some irrelevant information > stripped off > > ~$ cat /proc/cpuinfo > processor : 0 > vendor_id : GenuineIntel > cpu family : 6 > model : 14 > model name : Genuine Intel(R) CPU T2400 @ 1.83GHz > stepping : 8 > cpu MHz : 1833.000 > cache size : 2048 KB > physical id : 0 > siblings : 2 > core id : 0 > cpu cores : 2 > > processor : 1 > vendor_id : GenuineIntel > cpu family : 6 > model : 14 > model name : Genuine Intel(R) CPU T2400 @ 1.83GHz > stepping : 8 > cpu MHz : 1833.000 > cache size : 2048 KB > physical id : 0 > siblings : 2 > core id : 1 > cpu cores : 2 > > ~$ uname -a > Linux Noi1-501468 2.6.27-9-generic #1 SMP Thu Nov 20 21:57:00 UTC 2008 > i686 GNU/Linux > > The config file for this kernel has the following settings > > CONFIG_SMP=y > CONFIG_SCHED_MC=y > CONFIG_SCHED_SMT=y > > > and yet this is status of interrupts > > ~$ cat /proc/interrupts > CPU0 CPU1 > 0: 1847795 0 IO-APIC-edge timer > 1: 3518 0 IO-APIC-edge i8042 > 4: 4 0 IO-APIC-edge > 8: 168 0 IO-APIC-edge rtc0 > 9: 15 0 IO-APIC-fasteoi acpi > 12: 30659 0 IO-APIC-edge i8042 > 14: 58736 0 IO-APIC-edge ata_piix > 15: 177814 0 IO-APIC-edge ata_piix > 16: 967299 0 IO-APIC-fasteoi [EMAIL PROTECTED]:0000:00:02.0 > 18: 7 0 IO-APIC-fasteoi yenta > 20: 423 0 IO-APIC-fasteoi uhci_hcd:usb1, ehci_hcd:usb5 > 21: 37050 0 IO-APIC-fasteoi uhci_hcd:usb2, HDA Intel > 22: 0 0 IO-APIC-fasteoi uhci_hcd:usb3 > 23: 0 0 IO-APIC-fasteoi uhci_hcd:usb4 > 219: 1407645 0 PCI-MSI-edge iwl3945 > 220: 223391 0 PCI-MSI-edge eth0 > NMI: 0 0 Non-maskable interrupts > LOC: 380806 1332287 Local timer interrupts > RES: 310807 321674 Rescheduling interrupts > CAL: 144202 161332 function call interrupts > TLB: 1281 1087 TLB shootdowns > SPU: 0 0 Spurious interrupts > ERR: 0 > MIS: 0 > > All interrupt processing happening only on CPU0. Installing older > irqbalance does not seem to be an option here. What could be the > reason. Is there a bug in APIC? Or am I missing something? > > -- > Regards, > Ranjan > > -- > To unsubscribe from this list: send an email with > "unsubscribe kernelnewbies" to [EMAIL PROTECTED] > Please read the FAQ at http://kernelnewbies.org/FAQ > >
