On Thu, May 14, 2015 at 12:29:21PM -0700, Andrew Honig wrote: >> >> BTW, what is the purpose of this series. If I understand it correctly, you only want to >> use the in-kernel lapic and leave the others (pic, ioapic) in userspace, what is the >> benefit of it? > >The purpose is to achieve the security benefit of removing some of the >interrupt handling into userspace, without incurring a significant >performance penalty. If you move the entire IRQCHIP into userspace, >we've seen perf impacts from 15-200% depending on the workload. With >this patch series, we're seeing perf penalty <1% on our tests (TCP_RR Why keep pic and ioapic in kernel space not get obvious benefit, what's the bottleneck? Regards, Wanpeng Li >latency, TCP throughput, and Disk I/O). See >(https://lwn.net/Articles/619332/) > >> >> Thanks, >> Feng >> >>> >-- >To unsubscribe from this list: send the line "unsubscribe kvm" in >the body of a message to majordomo@xxxxxxxxxxxxxxx >More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
