Re: [PATCH] irq/affinity: Assign all CPUs a vector

[Sagi Grimberg]

> The number of vectors to assign needs to be adjusted for each node such
> that it doesn't exceed the number of CPUs in that node. This patch
> recalculates the vector assignment per-node so that we don't try to
> assign more vectors than there are CPUs. When that previously happened,
> the cpus_per_vec was calculated to be 0, so many vectors had no CPUs
> assigned. This then goes on to fail to allocate descriptors due to
> empty masks, leading to an unoptimal spread.

Can you give a specific (numeric) example where this happens? I'm having
a little trouble following the logical change here.