On Apr 9, 2015 8:20 AM, "John Moser" <<a href="mailto:john.r.moser@gmail.com">john.r.moser@gmail.com</a>> wrote: > > IRQbalance keeps all of the IRQ requests from backing up on a single > CPU. It tries to balance this out in an intelligent way accross all the > CPUs and, when possible, puts the IRQ processing as close to the process > as possible. > > On NUMA systems, you may want numad. I believe irqbalance exits if it > detects NUMA. > I see. Splitting interrupt handling evenly between CPUs. That is of course, there are multiple CPUs. How do I know my kernel is using irqbalance? > On 04/09/2015 08:14 AM, Istimsak Abdulbasir wrote: > > What is the irqbalance and what was the reason for using it? > > > > On Apr 9, 2015 8:09 AM, "Daniel J Blueman" <<a href="mailto:daniel@quora.org">daniel@quora.org</a> > > <mailto:<a href="mailto:daniel@quora.org">daniel@quora.org</a>>> wrote: > > > > Checked with Vivid beta on Intel i5 hardware, and it seems interrupt > > distribution doesn't change when I boot with irqbalance running [1], > > or after purging it and rebooting [2]. > > > > Finally, it can't second guess MSI interrupt setup better than the > > APIC driver and adds a unnecessary layer of 'intelligence'. I don't > > see any case common enough to warrant deploying it by default. > > > > Anyone against removing it? > > > > Dan > > > > -- [1] > > > > root@nuc:~# cat /proc/interrupts > > CPU0 CPU1 CPU2 CPU3 > > 0: 18 0 0 0 IR-IO-APIC-edge > > timer > > 1: 1 1 0 1 IR-IO-APIC-edge > > i8042 > > 7: 9 0 0 0 IR-IO-APIC-edge > > 8: 0 0 0 1 IR-IO-APIC-edge > > rtc0 > > 9: 3 0 0 0 > > IR-IO-APIC-fasteoi acpi > > 12: 1 2 1 0 IR-IO-APIC-edge > > i8042 > > 23: 11 1 15 6 IR-IO-APIC > > 23-fasteoi ehci_hcd:usb3 > > 40: 0 0 0 0 DMAR_MSI-edge > > dmar0 > > 41: 0 0 0 0 DMAR_MSI-edge > > dmar1 > > 42: 0 0 0 0 IR-PCI-MSI-edge > > PCIe PME > > 43: 0 0 0 0 IR-PCI-MSI-edge > > PCIe PME > > 44: 87 25 95 23 IR-PCI-MSI-edge > > xhci_hcd > > 45: 2740 4911 4405 14870 IR-PCI-MSI-edge > > 0000:00:1f.2 > > 46: 10 10 2504 3 IR-PCI-MSI-edge > > eth0 > > 47: 12 1 1 0 IR-PCI-MSI-edge > > mei_me > > 48: 8 14 3 1 IR-PCI-MSI-edge > > iwlwifi > > 49: 496 594 290 331 IR-PCI-MSI-edge > > i915 > > 50: 197 80 4 39 IR-PCI-MSI-edge > > snd_hda_intel > > 51: 721 0 0 28 IR-PCI-MSI-edge > > snd_hda_intel > > NMI: 1 1 0 1 Non-maskable > > interrupts > > LOC: 30046 19983 13391 18318 Local timer > > interrupts > > SPU: 0 0 0 0 Spurious interrupts > > PMI: 1 1 0 1 Performance > > monitoring interrupts > > IWI: 0 0 0 0 IRQ work interrupts > > RTR: 2 0 0 0 APIC ICR read retries > > RES: 943 1130 618 693 Rescheduling > > interrupts > > CAL: 840 699 674 747 Function call > > interrupts > > TLB: 198 205 286 1241 TLB shootdowns > > TRM: 0 0 0 0 Thermal event > > interrupts > > THR: 0 0 0 0 Threshold APIC > > interrupts > > MCE: 0 0 0 0 Machine check > > exceptions > > MCP: 4 4 4 4 Machine check polls > > HYP: 0 0 0 0 Hypervisor callback > > interrupts > > ERR: 9 > > MIS: 0 > > > > -- [2] > > > > root@nuc:~# cat /proc/interrupts > > CPU0 CPU1 CPU2 CPU3 > > 0: 20 0 0 0 IR-IO-APIC-edge > > timer > > 1: 1 0 1 1 IR-IO-APIC-edge > > i8042 > > 7: 11 0 0 0 IR-IO-APIC-edge > > 8: 0 0 0 1 IR-IO-APIC-edge > > rtc0 > > 9: 3 0 0 0 > > IR-IO-APIC-fasteoi acpi > > 12: 3 0 1 0 IR-IO-APIC-edge > > i8042 > > 23: 15 10 10 0 IR-IO-APIC > > 23-fasteoi ehci_hcd:usb3 > > 40: 0 0 0 0 DMAR_MSI-edge > > dmar0 > > 41: 0 0 0 0 DMAR_MSI-edge > > dmar1 > > 42: 0 0 0 0 IR-PCI-MSI-edge > > PCIe PME > > 43: 0 0 0 0 IR-PCI-MSI-edge > > PCIe PME > > 44: 48 9 98 11 IR-PCI-MSI-edge > > xhci_hcd > > 45: 3592 754 4633 1272 IR-PCI-MSI-edge > > 0000:00:1f.2 > > 46: 37 23 89 13 IR-PCI-MSI-edge > > eth0 > > 47: 14 0 0 0 IR-PCI-MSI-edge > > mei_me > > 48: 291 0 4 25 IR-PCI-MSI-edge > > snd_hda_intel > > 49: 12 16 6 0 IR-PCI-MSI-edge > > iwlwifi > > 50: 246 132 154 288 IR-PCI-MSI-edge > > i915 > > 51: 25 673 13 42 IR-PCI-MSI-edge > > snd_hda_intel > > NMI: 0 0 0 0 Non-maskable > > interrupts > > LOC: 1041 1680 928 964 Local timer > > interrupts > > SPU: 0 0 0 0 Spurious interrupts > > PMI: 0 0 0 0 Performance > > monitoring interrupts > > IWI: 0 0 1 0 IRQ work interrupts > > RTR: 3 0 0 0 APIC ICR read retries > > RES: 374 517 311 305 Rescheduling > > interrupts > > CAL: 638 640 679 609 Function call > > interrupts > > TLB: 1628 93 49 110 TLB shootdowns > > TRM: 0 0 0 0 Thermal event > > interrupts > > THR: 0 0 0 0 Threshold APIC > > interrupts > > MCE: 0 0 0 0 Machine check > > exceptions > > MCP: 2 2 2 2 Machine check polls > > HYP: 0 0 0 0 Hypervisor callback > > interrupts > > ERR: 11 > > MIS: 0 > > -- > > Daniel J Blueman > > > > -- > > Ubuntu-devel-discuss mailing list > > <a href="mailto:Ubuntu-devel-discuss@lists.ubuntu.com">Ubuntu-devel-discuss@lists.ubuntu.com</a> > > <mailto:<a href="mailto:Ubuntu-devel-discuss@lists.ubuntu.com">Ubuntu-devel-discuss@lists.ubuntu.com</a>> > > Modify settings or unsubscribe at: > > <a href="https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss">https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss</a> > > > > > > > > -- > Ubuntu-devel-discuss mailing list > <a href="mailto:Ubuntu-devel-discuss@lists.ubuntu.com">Ubuntu-devel-discuss@lists.ubuntu.com</a> > Modify settings or unsubscribe at: <a href="https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss">https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel-discuss</a>