From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mailrelay108.isp.belgacom.be (mailrelay108.isp.belgacom.be [195.238.20.135]) by huchra.bufferbloat.net (Postfix) with ESMTP id AC27421FAA1 for ; Wed, 8 Jul 2015 09:14:45 -0700 (PDT) X-Belgacom-Dynamic: yes X-Cloudmark-SP-Filtered: true X-Cloudmark-SP-Result: v=1.1 cv=E12Nk8Bf0hMlwhhcPGlCWJx/tbvGdtmOO6CYG/XBrkw= c=1 sm=2 a=gCGlv7sVAAAA:8 a=eW-IbUhgUPv0GE2TsXUA:9 a=QEXdDO2ut3YA:10 a=Prqojwohwq0A:10 a=-jjZi5UMItAA:10 a=eQ-H5kqaKlEA:10 a=yVbdS3uxqaMA:10 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2AYBQAZTJ1V/y4m9FFcFoJ8VGCDIK9iik0JgW+FcQQCAoFYORQBAQEBAQEBgQqEJAEBBCMzBhwRCwsNAgIFFgsCAgkDAgECAREWHhMIAQGIFAEZAQi3L4FrjikKGYELhHoBAQEHAQEBARoEgSGKKoUNFoJSgUMBBJQji36IQJAiJoN9PDEBAYJJAQEB Received: from 46.38-244-81.adsl-dyn.isp.belgacom.be (HELO zotac.xperim.be) ([81.244.38.46]) by relay.skynet.be with ESMTP; 08 Jul 2015 18:14:37 +0200 Received: from [192.168.1.172] (mordor.xperim.be [192.168.1.172]) by zotac.xperim.be (8.14.4/8.14.4/Debian-2ubuntu2.1) with ESMTP id t68GBsOP027848 for ; Wed, 8 Jul 2015 18:11:55 +0200 Message-ID: <559D4BCA.5040907@gmail.com> Date: Wed, 08 Jul 2015 18:11:54 +0200 From: Jan Ceuleers User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: bloat@lists.bufferbloat.net References: <20150708102317.A8994406057@ip-64-139-1-69.sjc.megapath.net> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Bloat] Graph of bloat X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Jul 2015 16:15:14 -0000 On 08/07/15 17:55, Dave Taht wrote: > That is a very interesting graph! Does ntp adjust system time backward > based on getting nearly all it's samples with well over a 1/2 second > of induced delay? If there is a consistent asymmetrical delay then yes. If the delay asymmetry is not persistent (but only occurs during up or downloads) then the so-called huff-n-puff filter can be used to factor it out. https://www.eecis.udel.edu/~mills/ntp/html/huffpuff.html Jan