On Mon, 2017-12-18 at 18:00 +0100, Mike Galbraith wrote: > On Mon, 2017-12-18 at 11:35 -0500, J. Bruce Fields wrote: > > > > Like I say, I don't really understand the issues here, so it's more a > > question than an objection.... (I don't know any reason a > > cond_resched() would be bad there.) > > Think of it this way: what all can be queued up behind that kworker > that is hogging CPU for huge swaths of time? It's not only userspace > that suffers. Bah, I'm gonna sound like a damn Baptist preacher, but I gotta say, latency matters just as much to an enterprise NOPREEMPT kernel and its users as it does to a desktop kernel and its users. For max throughput, you don't want to do work in _tiny_ quantum, because you then lose throughput due to massive cache trashing and scheduling overhead, but latency still does matter, and not just a little. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
