Slower performance with custom NUMA environment after upgrade from SLES11.SP2 to SLES11.SP3

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Environment

SUSE Linux Enterprise Server 11 Service Pack 2 (SLES 11 SP2)
SUSE Linux Enterprise Server 11 Service Pack 3 (SLES 11 SP3)

Situation

Experiencing very noticible degredation in performance of a customized NUMA set up running on DELL R810 hardware after going from SLES11 SP2 (3.0.101-0.7.17) to SLES11 SP3 (3.0.101-0.21)

DELL R820 hardware does not have the same slowness after upgrading and running the same custom NUMA setup.

Resolution

At the console run the following commands:

kill -9 irqbalance

for irq in `awk '/TxRx/{print $1+0}' < /proc/interrupts` do echo "0-1" > /proc/irq/$irq/smp_affinity_list done

Cause

Additional Information

If these commands return the performace to SLES11 SP2 levels then you can add them to the /etc/init.d/after.local file. after.local doesn’t exist by default, but it will get executed by /etc/init.d/rc if it does exist so you can create one.

Disclaimer

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