Bad system performance on Altix machines

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Environment

SUSE Linux Enterprise Server 10

Situation

Only on: iA64
After a kernel update to version 2.6.16.60-0.33 system performance on SGI Altix machines is dropping.

Resolution

Disable irqbalancer for this machine by running

rcirq_balancer stop

To disable the irq_balancer permanently use

chkconfig -d irq_balancer

or simply uninstall the package irqbalance.

Additional Information

The kernel update to 2.6.16.60-0.33 introduced automatic enablement of the irq_balancer. On SGI Altix interrupt balancing is done by the hardware. Therefore a software balancer is not needed and even has negative impact on these machines.

Disclaimer

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