[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores
From: |
Michael S. Tsirkin |
Subject: |
Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores |
Date: |
Tue, 13 Nov 2012 18:22:56 +0200 |
On Tue, Nov 13, 2012 at 12:49:03PM +0100, Peter Lieven wrote:
>
> On 09.11.2012 19:03, Peter Lieven wrote:
> >Remark:
> >If i disable interrupts on CPU1-3 for virtio the performance is ok again.
> >
> >Now we need someone with deeper knowledge of the in-kernel irqchip and the
> >virtio/vhost driver development to say if this is a regression in qemu-kvm
> >or a problem with the old virtio drivers if they receive the interrupt on
> >different CPUs.
> anyone?
Looks like the problem is not in the guest: I tried ubuntu guest
on a rhel host, I got 8GB/s with vhost and 4GB/s without
on a host to guest banchmark.
>
> >
> >Peter Lieven wrote:
> >>it seems that with in-kernel irqchip the interrupts are distributed across
> >>all vpcus. without in-kernel irqchip all interrupts are on cpu0. maybe
> >>this is related.
> >>
> >>without inkernel irqchip
> >> CPU0 CPU1 CPU2 CPU3
> >> 0: 16 0 0 0 IO-APIC-edge timer
> >> 1: 23 0 0 0 IO-APIC-edge i8042
> >> 4: 1 0 0 0 IO-APIC-edge
> >> 6: 4 0 0 0 IO-APIC-edge
> >>floppy
> >> 7: 0 0 0 0 IO-APIC-edge
> >>parport0
> >> 8: 0 0 0 0 IO-APIC-edge rtc0
> >> 9: 0 0 0 0 IO-APIC-fasteoi acpi
> >> 11: 76 0 0 0 IO-APIC-fasteoi
> >>uhci_hcd:usb1
> >> 12: 102 0 0 0 IO-APIC-edge i8042
> >> 14: 0 0 0 0 IO-APIC-edge
> >>ata_piix
> >> 15: 16881 0 0 0 IO-APIC-edge
> >>ata_piix
> >> 24: 0 0 0 0 PCI-MSI-edge
> >>virtio1-config
> >> 25: 5225 0 0 0 PCI-MSI-edge
> >>virtio1-requests
> >> 26: 0 0 0 0 PCI-MSI-edge
> >>virtio0-config
> >> 27: 72493 0 0 0 PCI-MSI-edge
> >>virtio0-input
> >>...
> >>
> >>with inkernel irqchip
> >> CPU0 CPU1 CPU2 CPU3
> >> 0: 16 0 0 0 IO-APIC-edge timer
> >> 1: 0 3 3 1 IO-APIC-edge i8042
> >> 4: 0 0 1 0 IO-APIC-edge
> >> 6: 1 0 1 2 IO-APIC-edge
> >>floppy
> >> 7: 0 0 0 0 IO-APIC-edge
> >>parport0
> >> 8: 0 0 0 0 IO-APIC-edge rtc0
> >> 9: 0 0 0 0 IO-APIC-fasteoi acpi
> >> 11: 7 9 4 1 IO-APIC-fasteoi
> >>uhci_hcd:usb1
> >> 12: 30 27 29 34 IO-APIC-edge i8042
> >> 14: 0 0 0 0 IO-APIC-edge
> >>ata_piix
> >> 15: 943 937 950 943 IO-APIC-edge
> >>ata_piix
> >> 24: 0 0 0 0 PCI-MSI-edge
> >>virtio0-config
> >> 25: 930 978 980 947 PCI-MSI-edge
> >>virtio0-input
> >> 26: 0 0 1 0 PCI-MSI-edge
> >>virtio0-output
> >> 27: 0 0 0 0 PCI-MSI-edge
> >>virtio1-config
> >> 28: 543 541 542 553 PCI-MSI-edge
> >>virtio1-requests
> >>...
> >>
> >>
> >
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, (continued)
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Dietmar Maurer, 2012/11/06
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Jan Kiszka, 2012/11/08
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/08
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Dietmar Maurer, 2012/11/08
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/08
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Dietmar Maurer, 2012/11/09
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/09
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/09
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/09
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores,
Michael S. Tsirkin <=
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Michael S. Tsirkin, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Dietmar Maurer, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Michael S. Tsirkin, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Michael S. Tsirkin, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Peter Lieven, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Michael S. Tsirkin, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Dietmar Maurer, 2012/11/13
- Re: [Qemu-devel] slow virtio network with vhost=on and multiple cores, Michael S. Tsirkin, 2012/11/13