From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-x236.google.com (mail-oi0-x236.google.com [IPv6:2607:f8b0:4003:c06::236]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id B762221FAD9 for ; Wed, 8 Jul 2015 08:55:42 -0700 (PDT) Received: by oiab3 with SMTP id b3so50763492oia.1 for ; Wed, 08 Jul 2015 08:55:41 -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:content-transfer-encoding; bh=+cetfFod95t3O6sNm0HsUA5/JZKQnLs/U6oCcMVFR6E=; b=QF/CwmRIgQSIprU4M0pKdLO9SQVRxuHJ9VISiv4N4s+9f6dhaLGfUalm9eYZW1goDd IXoSUguaRVEkfKfycqCuj6vkMpRT5ZIILrS/UFXGPcBykTZB+P6+Zgv8XzqzHpa4SKW7 1RmaIS51DfB9UjQgxJXJ6DS5267p4qAf7A9VQYIu9c6zW88aDaS80IafIyyQCfyrznIB OAOE4kcBuwaori1hbbdVN0W70RONwjsK3ybmG65z0WpSRO3AF4+ZsR5njUyHQQfReXT7 yvU7K1k/LriX2zV3krADnM9DtXHOJzNxMfSHGWoNRMMfABYoF7G1uAjpBflfsQ1clCCX pSiA== MIME-Version: 1.0 X-Received: by 10.60.62.204 with SMTP id a12mr10764531oes.39.1436370941310; Wed, 08 Jul 2015 08:55:41 -0700 (PDT) Received: by 10.202.107.9 with HTTP; Wed, 8 Jul 2015 08:55:41 -0700 (PDT) In-Reply-To: <20150708102317.A8994406057@ip-64-139-1-69.sjc.megapath.net> References: <20150708102317.A8994406057@ip-64-139-1-69.sjc.megapath.net> Date: Wed, 8 Jul 2015 08:55:41 -0700 Message-ID: From: Dave Taht To: Hal Murray Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Cc: bloat 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 15:56:11 -0000 On Wed, Jul 8, 2015 at 3:23 AM, Hal Murray wrote: > I was monitoring Google's time servers over the recent leap second. That > graph happened to include some good examples of bloat. > > http://www.megapathdsl.net/~hmurray/bloat/google-off-smear-bloat.png > > I have a slow DSL line with almost 4 seconds of buffering. > > The blobs at -20 and -15 seconds are typical of a single large download. = The > column at -6 seconds is typical of several active connections. 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? Interestingly (or disturbingly) - dnsmasq just found and fixed a crash bug that happened when time ran backwards. I can imagine a few other core utilities/protocols/system services that should be checked for bad behavior in this case. http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2015q3/009701.html > > -- > These are my opinions. I hate spam. > > > > _______________________________________________ > Bloat mailing list > Bloat@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/bloat --=20 Dave T=C3=A4ht worldwide bufferbloat report: http://www.dslreports.com/speedtest/results/bufferbloat And: What will it take to vastly improve wifi for everyone? https://plus.google.com/u/0/explore/makewififast