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I'm trying to get my Xen Dom0 distributing the irqs in an smp enviroment. As far as I know there are 2 Options:

  • Use irqbalance
  • Configure the kernel without cpu hotplug support

My System is Debian Squeeze, Xen 4.0.4, Kernel 3.2.31.

My Problem is:

  • irqbalance segfaults due to a changed /proc/irq* layout or irq0 missing (this seems to be a very old bug existing since Lenny)
  • To configure a kernel without cpu hotplug support you must disable cpu powermanagement which seems to be impossible through the standard wys (make config / make menuconfig) - the option CONFIG_PM simply defaults to "Y".

Any idea anyone on how to get a debian dom0 kernel with a proper irq distribution?

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up vote 0 down vote accepted

Ingrid says: You shall limit your cpus to use irqbalance:

XEN commandline failing to start irqbalance under squeeze:

/boot/xen-4.0.4.gz dom0_mem=2597152 no-bootscrub dom0_vcpus_pin

Working commandline:

/boot/xen-4.0.4.gz dom0_mem=2597152 no-bootscrub dom0_max_vcpus=2 dom0_vcpus_pin

Tested with 3.2.30 and 3.2.31.

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