From owner-freebsd-net@FreeBSD.ORG Tue May 8 00:25:30 2012 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id C33461065670 for ; Tue, 8 May 2012 00:25:30 +0000 (UTC) (envelope-from jfvogel@gmail.com) Received: from mail-wi0-f178.google.com (mail-wi0-f178.google.com [209.85.212.178]) by mx1.freebsd.org (Postfix) with ESMTP id 4F8A98FC08 for ; Tue, 8 May 2012 00:25:30 +0000 (UTC) Received: by wibhq2 with SMTP id hq2so96396wib.13 for ; Mon, 07 May 2012 17:25:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=QKAl1JGrI3G0psouj76VbIsl0/8WZ1yfj8mrwsPAqVM=; b=QplbJ9yVPkX0Tj7l3mcJNb99qcMnhVm8mg+Q1KCOfxnHWgjDOl8r1EhvwT/0MvXw3x +zUsw74YfdGhOQc0iNoKHQ5Y0fmBHy5x3abQSNK2LxZO2zr1W/Me0Em9ihTeHtKNammj maQfXvPW2/udcUc2UPlov4gYrAo8dn3bPl97SPOwPB1jyeZ0NOxHtSs/G1LV+PypwBCI qkFKVn/M8Y8KuaqUIl9j/di6HqHU4zTTMwzycA3SC0MPQvgn4FPipxJq3aqX6OLsfJDN J4ow2w66eZnFQ4nmJBb8/Th9QjUi45qklsdhz1tS9CqfaEEU6Y7hUSartfnXERoI4hOc VbPA== MIME-Version: 1.0 Received: by 10.180.24.35 with SMTP id r3mr39544432wif.7.1336436729158; Mon, 07 May 2012 17:25:29 -0700 (PDT) Received: by 10.180.7.103 with HTTP; Mon, 7 May 2012 17:25:29 -0700 (PDT) In-Reply-To: References: Date: Mon, 7 May 2012 17:25:29 -0700 Message-ID: From: Jack Vogel To: Vijay Singh Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-net@freebsd.org Subject: Re: What does adapter->stats.mpc[] report for ixgbe? X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 May 2012 00:25:30 -0000 This is 'missed packet count', the index has actually been misinterpreted in the code for a while, it was mistakenly associated with queues, but its really per packet buffer, and there are only more than one when there are multiple traffic classes (ala DCB). Even so, only MPC(0) should get incremented anyway. Here is a description: Packets are missed when the receive FIFO has insufficient space to store the incoming packet. This may be caused due to insufficient buffers allocated, or because there is insufficient bandwidth on the IO bus. Events setting this counter also set the receiver overrun interrupt (RXO). These registers do not increment if receive is not enabled and count only packets that would have been posted to the SW driver. Hope this illuminates :) Cheers! Jack On Mon, May 7, 2012 at 5:09 PM, Vijay Singh wrote: > Hi, a question for jfv@ or whoever else is familiar with the ixgbe > driver - I am looking at a system where the adapter reports a large > number of ierrors that I traced to this stat. What does this mean? > Intuitively it seems like the receive ring isn't being drained fast > enough but wanted to confirm with the experts. > > -vijay > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org" >