* Hardware Interrupt Balancing
@ 2010-03-25 1:11 James Lamanna
2010-03-25 10:36 ` Alejandro Riveira Fernández
0 siblings, 1 reply; 3+ messages in thread
From: James Lamanna @ 2010-03-25 1:11 UTC (permalink / raw)
To: linux-kernel
Hi,
I have a Dual Xeon (single core each w/HT) machine and I noticed the
other day that interrupts are not
being balanced across the 2 processors:
CPU0 CPU1 CPU2 CPU3
0: 306 0 0 3254413993 IO-APIC-edge timer
1: 0 0 0 13468 IO-APIC-edge i8042
8: 0 0 0 3 IO-APIC-edge rtc
9: 0 0 0 0 IO-APIC-level acpi
12: 0 0 0 4 IO-APIC-edge i8042
169: 0 0 0 0 IO-APIC-level uhci_hcd:usb2
177: 0 0 0 16743166 IO-APIC-level ata_piix
185: 0 0 0 1 IO-APIC-level ehci_hcd:usb1
193: 0 0 0 0 IO-APIC-level uhci_hcd:usb3
201: 0 0 0 1867922172 IO-APIC-level eth0
209: 0 0 0 3254690559 IO-APIC-level wct4xxp
NMI: 1 0 0 0
LOC: 3255261535 3255261540 3255261549 3255220504
ERR: 0
MIS: 0
However the cpu_affinity of say, wct4xxp is:
# cat /proc/irq/209/smp_affinity
0000000f
Is there something (CPU Hotplug?) preventing the hardware interrupts
from being balanced across both CPUs?
The kernel version is 2.6.18 (i686) (this is an older machine that is
a PSTN<->SIP gateway).
Thanks.
-- James
Please CC me for I am not subscribed.
^ permalink raw reply [flat|nested] 3+ messages in thread* Re: Hardware Interrupt Balancing
2010-03-25 1:11 Hardware Interrupt Balancing James Lamanna
@ 2010-03-25 10:36 ` Alejandro Riveira Fernández
2010-03-29 20:14 ` James Lamanna
0 siblings, 1 reply; 3+ messages in thread
From: Alejandro Riveira Fernández @ 2010-03-25 10:36 UTC (permalink / raw)
To: James Lamanna; +Cc: linux-kernel
El Wed, 24 Mar 2010 18:11:36 -0700
James Lamanna <jlamanna@gmail.com> escribió:
> Hi,
> I have a Dual Xeon (single core each w/HT) machine and I noticed the
> other day that interrupts are not
> being balanced across the 2 processors:
>
> CPU0 CPU1 CPU2 CPU3
> 0: 306 0 0 3254413993 IO-APIC-edge timer
> 1: 0 0 0 13468 IO-APIC-edge i8042
> 8: 0 0 0 3 IO-APIC-edge rtc
> 9: 0 0 0 0 IO-APIC-level acpi
> 12: 0 0 0 4 IO-APIC-edge i8042
> 169: 0 0 0 0 IO-APIC-level uhci_hcd:usb2
> 177: 0 0 0 16743166 IO-APIC-level ata_piix
> 185: 0 0 0 1 IO-APIC-level ehci_hcd:usb1
> 193: 0 0 0 0 IO-APIC-level uhci_hcd:usb3
> 201: 0 0 0 1867922172 IO-APIC-level eth0
> 209: 0 0 0 3254690559 IO-APIC-level wct4xxp
> NMI: 1 0 0 0
> LOC: 3255261535 3255261540 3255261549 3255220504
> ERR: 0
> MIS: 0
>
> However the cpu_affinity of say, wct4xxp is:
> # cat /proc/irq/209/smp_affinity
> 0000000f
Maybe you just need to run irqbalance http://www.irqbalance.org/
« sudo aptitude install irqbalance » in Debian system
>
> Is there something (CPU Hotplug?) preventing the hardware interrupts
> from being balanced across both CPUs?
> The kernel version is 2.6.18 (i686) (this is an older machine that is
> a PSTN<->SIP gateway).
>
> Thanks.
>
> -- James
>
> Please CC me for I am not subscribed.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: Hardware Interrupt Balancing
2010-03-25 10:36 ` Alejandro Riveira Fernández
@ 2010-03-29 20:14 ` James Lamanna
0 siblings, 0 replies; 3+ messages in thread
From: James Lamanna @ 2010-03-29 20:14 UTC (permalink / raw)
To: Alejandro Riveira Fernández; +Cc: linux-kernel@vger.kernel.org
--James
On Mar 25, 2010, at 3:36, Alejandro Riveira Fernández <ariveira@gmail.co
m> wrote:
> El Wed, 24 Mar 2010 18:11:36 -0700
> James Lamanna <jlamanna@gmail.com> escribió:
>
>> Hi,
>> I have a Dual Xeon (single core each w/HT) machine and I noticed the
>> other day that interrupts are not
>> being balanced across the 2 processors:
>>
>> CPU0 CPU1 CPU2 CPU3
>> 0: 306 0 0 3254413993 IO-APIC-edge
>> timer
>> 1: 0 0 0 13468 IO-APIC-edge
>> i8042
>> 8: 0 0 0 3 IO-APIC-edge rtc
>> 9: 0 0 0 0 IO-APIC-level acpi
>> 12: 0 0 0 4 IO-APIC-edge
>> i8042
>> 169: 0 0 0 0 IO-APIC-level
>> uhci_hcd:usb2
>> 177: 0 0 0 16743166 IO-APIC-level
>> ata_piix
>> 185: 0 0 0 1 IO-APIC-level
>> ehci_hcd:usb1
>> 193: 0 0 0 0 IO-APIC-level
>> uhci_hcd:usb3
>> 201: 0 0 0 1867922172 IO-APIC-level
>> eth0
>> 209: 0 0 0 3254690559 IO-APIC-level
>> wct4xxp
>> NMI: 1 0 0 0
>> LOC: 3255261535 3255261540 3255261549 3255220504
>> ERR: 0
>> MIS: 0
>>
>> However the cpu_affinity of say, wct4xxp is:
>> # cat /proc/irq/209/smp_affinity
>> 0000000f
>
> Maybe you just need to run irqbalance http://www.irqbalance.org/
> « sudo aptitude install irqbalance » in Debian system
I do not want to use irq balance because everytime irqbalance moves
the CPU of my PRI card, there is a hiccup in voice calls.
I manually moved the interrupts for the wct4xxp to CPU0 using
smp_affinity = 1.
However today I got a lot of soft lockups on CPU0 due to asterisk in
udp_sendmsg() - unsure if moving the interrupt caused this...could it?
Thanks.
-- James
>
^ permalink raw reply [flat|nested] 3+ messages in thread
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