From mboxrd@z Thu Jan 1 00:00:00 1970 From: Or Gerlitz Subject: Re: [PATCH 5/5] IB/srp: Optimize completion queue polling Date: Tue, 8 Jul 2014 12:24:27 +0300 Message-ID: <53BBB8CB.2010300@mellanox.com> References: <53B55E55.5040907@acm.org> <53B55F1F.6000704@acm.org> <53B67B0E.5070004@acm.org> <53BBA79A.9000000@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <53BBA79A.9000000-HInyCGIudOg@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Bart Van Assche , Or Gerlitz Cc: Roland Dreier , Sagi Grimberg , Sebastian Parschauer , David Dillow , linux-rdma List-Id: linux-rdma@vger.kernel.org On 08/07/2014 11:11, Bart Van Assche wrote: > e might each be referring to different concepts here. What you are > referring to is average response time for QD > 1. What I was referring > to is average response time for QD = 1. The measurements I ran with fio > have shown that the response time for QD = 1 is lower when processing > completions in interrupt context compared to processing interrupts in > softirq context. I see, but wait, I had few arguments... among them the fact that the vast majority if not the entire set of networking drivers live well with this CS to softirqD over-head also for their ping-ping (~ QD=1) latency tests and their latency is ~3x small vs block drivers. Or. -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html