On Mon, Dec 15, 2014 at 11:51:46PM -0500, Sasha Levin wrote: > I'm not sure if you've caught up on the RCU stall issue we've been trying > to track down (https://lkml.org/lkml/2014/11/14/656), but could this "funny" > balancing behaviour be "funny" enough to cause a stall?
Typically not, the worst degenerate modes are either running everything on one cpu or constantly migrating tasks. Both suck performance wise, but are 'valid' modes of operation. RCU stalls require not actually getting to userspace or otherwise delaying grace periods for egregious amounts of time. The only way I can see that happening is a load-balance pass not finishing at all, and then you'd consistently get stack traces from inside the balancer -- and I'm not seeing that in the email referenced. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
