From owner-freebsd-questions@FreeBSD.ORG Fri Nov 20 21:35:25 2009 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id CB7511065672 for ; Fri, 20 Nov 2009 21:35:25 +0000 (UTC) (envelope-from brett@lariat.net) Received: from lariat.net (lariat.net [66.119.58.2]) by mx1.freebsd.org (Postfix) with ESMTP id 4F00D8FC13 for ; Fri, 20 Nov 2009 21:35:24 +0000 (UTC) Received: (from brett@localhost) by lariat.net (8.9.3/8.9.3) id OAA18537 for questions@freebsd.org; Fri, 20 Nov 2009 14:35:22 -0700 (MST) Date: Fri, 20 Nov 2009 14:35:22 -0700 (MST) From: Brett Glass Message-Id: <200911202135.OAA18537@lariat.net> To: questions@freebsd.org Cc: Subject: kern.polling.lost_polls X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 20 Nov 2009 21:35:25 -0000 Everyone: I've been experimenting with using device polling on a router with six Ethernet interfaces that handles lots of traffic. I turned polling on, and set HZ=4000 to minimize latency and ensure that enough time was allocated to handle all of the incoming packets. But the sysctl variable kernel.polling.lost_polls keeps incrementing! The documentation of this variable isn't very good, so I am not sure what this means. Does it mean that I should set kern.hz lower (perhaps to 2000) and kern.polling.burst_max higher? Or that running the interfaces in interrupt-driven mode would be more effective? How can I tell? (Feel free to ask for more information about the hardware or kernel config if it would help you to provide a good answer.) --Brett Glass