From owner-freebsd-net@FreeBSD.ORG Wed Apr 16 14:13:12 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 6B39A1065678 for ; Wed, 16 Apr 2008 14:13:12 +0000 (UTC) (envelope-from rrs@cisco.com) Received: from sj-iport-1.cisco.com (sj-iport-1.cisco.com [171.71.176.70]) by mx1.freebsd.org (Postfix) with ESMTP id ECF5D8FC18 for ; Wed, 16 Apr 2008 14:13:11 +0000 (UTC) (envelope-from rrs@cisco.com) Received: from sj-dkim-4.cisco.com ([171.71.179.196]) by sj-iport-1.cisco.com with ESMTP; 16 Apr 2008 07:03:54 -0700 Received: from sj-core-5.cisco.com (sj-core-5.cisco.com [171.71.177.238]) by sj-dkim-4.cisco.com (8.12.11/8.12.11) with ESMTP id m3GE3sEI019455; Wed, 16 Apr 2008 07:03:54 -0700 Received: from xbh-sjc-211.amer.cisco.com (xbh-sjc-211.cisco.com [171.70.151.144]) by sj-core-5.cisco.com (8.13.8/8.13.8) with ESMTP id m3GE3srT002244; Wed, 16 Apr 2008 14:03:54 GMT Received: from xfe-sjc-211.amer.cisco.com ([171.70.151.174]) by xbh-sjc-211.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 16 Apr 2008 07:03:53 -0700 Received: from rrs.local ([171.68.225.134]) by xfe-sjc-211.amer.cisco.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 16 Apr 2008 07:03:53 -0700 Message-ID: <48060748.1090807@cisco.com> Date: Wed, 16 Apr 2008 10:03:52 -0400 From: Randall Stewart User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.12) Gecko/20080201 SeaMonkey/1.1.8 MIME-Version: 1.0 To: "Rahman, Md Sazzadur" References: <7059EA19D7837E44A3BA7DAB464944B37FDA715193@XMAIL5.sooner.net.ou.edu> In-Reply-To: <7059EA19D7837E44A3BA7DAB464944B37FDA715193@XMAIL5.sooner.net.ou.edu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 16 Apr 2008 14:03:53.0687 (UTC) FILETIME=[B447BE70:01C89FCA] DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; l=1703; t=1208354634; x=1209218634; c=relaxed/simple; s=sjdkim4002; h=Content-Type:From:Subject:Content-Transfer-Encoding:MIME-Version; d=cisco.com; i=rrs@cisco.com; z=From:=20Randall=20Stewart=20 |Subject:=20Re=3A=20A=20query=20regarding=20SCTP=20congesti on=20control |Sender:=20; bh=2Y8lG9BWQt0ZNvmE/V6yU6FT6taAvsLxNk0B3wXmE5M=; b=Z7nxZWhmFZbh30kN2xqty6jzVaAZwkC64rb5TjRwV0vYY3nABcdZ59Gq6C +qTMjOWEgtE6s3KiE4SqD243Pj2QxSFGXyF6ALGe6cWN/dZVOT1FNe8H5XqE /U4sgqrz7+; Authentication-Results: sj-dkim-4; header.From=rrs@cisco.com; dkim=pass ( sig from cisco.com/sjdkim4002 verified; ); Cc: "freebsd-net@freebsd.org" Subject: Re: A query regarding SCTP congestion control 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: Wed, 16 Apr 2008 14:13:12 -0000 Rahman, Md Sazzadur wrote: > Hi, I would like to get the values of SCTP congestion control > algorithm variables (cwnd, ssthresh, flightsize and pba) from any > SCTP based application in runtime for research purpose. Does any API > exist in SCTP for that? Do I need to dig the SCTP code in kernel to > get the values? There is a socket option to get the cwnd. However, I think what you really want is some of the researchish tracing stuff that SCTP provides. You can actually get a real time trace of the cwnd/flight etc via the various logging functions. You basically must compile this as an option.. have to go look at the options.. And then you can either use ktrace (which I don't recommend since it turns on to much overhead in the kernel) or you can use SCTP_LOCAL_TRACE_BUF This will put it into a piece of memory only for SCTP and not turn on all the other ktrace points. After you enable the logging in your compile you must turn on the logging level.. SCTP_CWND_LOGGING_ENABLE woudl be my recommendation. It gives you a real time up/down growth of the cwnd/flight/rwnd I think I wrote a "how to" somewhere.. let me go look.. R > > I will appreciate any help in this regard. > > Best Regards, Md Sazzadur Rahman Graduate Student, School of Computer > Science, University of Oklahoma, Norman, Oklahoma, USA > > _______________________________________________ > 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" > -- Randall Stewart NSSTG - Cisco Systems Inc. 803-345-0369 803-317-4952 (cell)