From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Chris Friesen" Subject: Re: questions on NAPI processing latency and dropped network packets Date: Thu, 10 Jan 2008 15:29:12 -0600 Message-ID: <47868E28.1070600@nortel.com> References: <478654C3.60806@nortel.com> <47866327.8090905@katalix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org To: James Chapman Return-path: Received: from zrtps0kn.nortel.com ([47.140.192.55]:52577 "EHLO zrtps0kn.nortel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752463AbYAJVac (ORCPT ); Thu, 10 Jan 2008 16:30:32 -0500 In-Reply-To: <47866327.8090905@katalix.com> Sender: netdev-owner@vger.kernel.org List-ID: James Chapman wrote: > What's changed in your application? Any real-time threads in there? > >>>From the top output below, looks like SigtranServices is consuming all > your CPU... There are two cpus, and SigtranServices is multithreaded with many threads. Most of these threads are affined to cpu0, a couple to cpu1. None of the threads are realtime. Top is showing 37% idle on cpu0, and 6% idle on cpu1, so not all the cpu is being consumed. However, I'm wondering if we're hitting bursty bits and we're just running out of time. I'm going to try a system with MAX_SOFTIRQ_RESTART bumped up a bit, and also enable profiling. Chris