On Thu, Nov 12, 2015 at 03:59:46PM -0500, Mohsin Zaidi wrote: > Hello, > > We?ve run into an irqbalance CPU banning issue that seems to be > present in version 1.0.4 as well as in newer versions 1.0.7 and 1.0.9. > > On an Oracle X5-2 with 72 cores, irqbalance keeps concentrating IRQs > from one interface (eth03) (the active slave in a bonded pair running > network traffic) on CPU 18/37 (more on #18), even though all CPUs but > 1/37 have been banned from IRQ processing. We?re seeing this on > multiple X5-2s. The interrupts are never directed to CPU 1. This does > not seem to be a problem with other 32 core servers we have. > > I?ve attached the top CPU list, /proc/interrupts for eth03, irqbalance > debug output, smp_affinity for eth03 IRQs (548-611), and the hardware > topology. > > Any help would be appreciated. Please let me know if I can provide any > additional information. > > Regards, > Mohsin A few initial questions Are you able to set irq affinity manually on these systems? And are you able to see those affinities take effect? I ask because the smp_affinity output you sent me makes it look like writes to that file for a given interrupt aren't getting picked up, and so the hardware is actually deciding where to steer interrupts. Have you tried using an upstream version of irqbalance? I ask because commit f1bf15ed7ea63a04c76da033b78f8ffc806d4517, which came out after 1.0.9 fixes a problem in which the --banirq option stopped working on a irq db reparsing. Neil
