Re: rcu stalls and soft lockups with recent kernels

[Mike Galbraith]

On Wed, 2016-03-16 at 12:15 -0400, Ion Badulescu wrote:
> Just following up to my own email:
> 
> It turns out that we can eliminate the RCU stalls by changing from 
> CONFIG_RCU_NOCB_CPU_ALL to CONFIG_RCU_NOCB_CPU_NONE. Letting each cpu 
> handle its own RCU callbacks completely fixes the problems for us.
> 
> Now, CONFIG_NO_HZ_FULL and CONFIG_RCU_NOCB_CPU_ALL is the default config 
> for fedora and rhel7. Ho-humm...

All RCU offloaded to CPU0 of a big box seems like a very bad idea.

	-Mike