[Lustre-discuss] socknal_sd00 100% lower?

[Brock Palen]

>
> echo 0 > /sys/modules/ksocklnd/{parameters}/enable_irq_affinity

I set the option,  'cat' confirms it was set, so far i see no effect  
(zero cpu time on 01)  but I will keep a eye on it.
>
> The "{parameters}" subdir is present or not, depending on the kernel
> version (yay consistency!).
>
> That said, it is implementation dependent on whether changing the
> parameter after the module is loaded has any effect.  I suspect in
> this case it will not have any effect because the kernel threads
> are already bound to their CPUs, but this isn't my strongest area.
>
> Maxim, Isaac, what are your thoughts about disabling IRQ affinity
> by default?  In the past this was important for maximizing performance
> with N CPUs and N ethernet NICs, but the CPUs have gotten much faster
> and more cores and I believe other customers have found better  
> performance
> with irq_affinity disabled.
>
> Cheers, Andreas
> --
> Andreas Dilger
> Sr. Staff Engineer, Lustre Group
> Sun Microsystems of Canada, Inc.
>
>
>