Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 6 Dec 2001 20:06:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 6 Dec 2001 20:06:50 -0500 Received: from mercury.Sun.COM ([192.9.25.1]:217 "EHLO mercury.Sun.COM") by vger.kernel.org with ESMTP id ; Thu, 6 Dec 2001 20:06:46 -0500 Message-ID: <3C1015EC.5B7316A0@sun.com> Date: Thu, 06 Dec 2001 17:05:48 -0800 From: Tim Hockin Organization: Sun Microsystems, Inc. X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.12C5_V i686) X-Accept-Language: en MIME-Version: 1.0 To: Jeff Garzik CC: Alan Cox , Linux Kernel Mailing List , arjanv@redhat.com, saw@sw-soft.com, sparker@sparker.net Subject: Re: [PATCH] eepro100 - need testers In-Reply-To: <3C10011A.A16E5287@mandrakesoft.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jeff Garzik wrote: > This patch got me thinking about net driver ring sizes in general. When > you are talking thousands of packets per second at 100 mbit, a larger > ring size than the average 32-64 seems to make sense too. Well, the math for teh very worst case is something like: 100,000,000 bits/sec /8 = 12500000 bytes/sec /64 bytes/ping = 195312.5 ping/sec /100 = 1953 ping/jiffy rounded to 2048 /2 = 1024 rx buffers per 1/2 jiffie. 1024 means you can withstand a wire-speed storm while interrupting twice per jiffy. -- Tim Hockin Systems Software Engineer Sun Microsystems, Cobalt Server Appliances thockin@sun.com - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/