Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935151AbdCWWtW (ORCPT ); Thu, 23 Mar 2017 18:49:22 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:34925 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751467AbdCWWtS (ORCPT ); Thu, 23 Mar 2017 18:49:18 -0400 MIME-Version: 1.0 In-Reply-To: References: <20170323211820.12615.88907.stgit@localhost.localdomain> <20170323220721.GA62356@ast-mbp.thefacebook.com> From: Eric Dumazet Date: Thu, 23 Mar 2017 15:49:08 -0700 Message-ID: Subject: Re: [net-next PATCH v2 0/8] Add busy poll support for epoll To: Alexander Duyck Cc: Alexei Starovoitov , Netdev , "linux-kernel@vger.kernel.org" , "Samudrala, Sridhar" , David Miller , linux-api@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 942 Lines: 26 On Thu, Mar 23, 2017 at 3:38 PM, Alexander Duyck wrote: > On Thu, Mar 23, 2017 at 3:07 PM, Alexei Starovoitov >> it all sounds awesome, but i cannot quite visualize the impact. >> Can you post some sample code/minibenchmark and numbers before/after? >> >> Thanks! >> > > Anything specific you are looking for? I can probably work with our > team internally to setup the benchmark in the next day or so. > > I've been doing most of my benchmarking at my desk with sockperf with > just one thread and multiple sockets and seeing some modest savings > with my round trip times dropping from something like 18 microseconds > on average to 8 microseconds for ping-pong tests. Same reduction for me, on 1000/1000 bytes RPC. 26 usec -> 16 usec per transaction (If you use sockperf, beware that it displays half round trips) Also note that the gains also depends on how the interrupt mitigation parameters are set.