From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id 80D0F138202 for ; Fri, 13 Sep 2013 18:39:50 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id BC0DAE0B00; Fri, 13 Sep 2013 18:39:45 +0000 (UTC) Received: from mail-qc0-f169.google.com (mail-qc0-f169.google.com [209.85.216.169]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id BA16FE0AFA for ; Fri, 13 Sep 2013 18:39:44 +0000 (UTC) Received: by mail-qc0-f169.google.com with SMTP id c9so1165102qcz.14 for ; Fri, 13 Sep 2013 11:39:44 -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 :content-type; bh=w3INHPhZPvJT0aFLx7J/waodaMzUAmjpXDsBbGB/FY8=; b=JZArZqJNRTG2knvALUlXUYH5JB/ytzdoSBruLpKmvh+dA9A5p+LGV5KqZsTEwDvzr1 KMhraAYVsB1oTrzz1K7sd/iSCUc3fiwiciBddmkUJUFF5Y9SLOIZmEWkWGaOAbFdtfaM ksSWu6Qj+jALLvSFSz+5HKFUvkyI3CXIkjSXmJb/Z/cniC6lhg8Ez2qTNhLUSzxVf8Zq c+bL13aB+vHwOSmKrMsk1gMzcadt90svdsga9pGJHDdMNNkoeQntlC19Co8oFlYCy4G9 LAnlI6n9beKXviICCblDUdU2QOxgZKyld0OQHq6vdycTxMr9/iENMKJyONuaUQmpfrZj zj9g== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 X-Received: by 10.229.47.71 with SMTP id m7mr27618444qcf.25.1379097583857; Fri, 13 Sep 2013 11:39:43 -0700 (PDT) Received: by 10.140.25.83 with HTTP; Fri, 13 Sep 2013 11:39:43 -0700 (PDT) In-Reply-To: <201309071641.59772.michaelkintzios@gmail.com> References: <201309031635.11591.michaelkintzios@gmail.com> <201309071641.59772.michaelkintzios@gmail.com> Date: Fri, 13 Sep 2013 11:39:43 -0700 Message-ID: Subject: Re: [gentoo-user] Can't ping remote system From: Grant To: Gentoo mailing list Content-Type: text/plain; charset=ISO-8859-1 X-Archives-Salt: b124d152-0d57-45d1-ab90-0267cf83e75e X-Archives-Hash: ee4f8a0946f2356913ea5e7bd29ce290 >> > +1 on Alan's hunch. I have not used Squid to comment on the specifics >> > and also Grant stated that another proxy gave him similar symptoms. >> > From my limited knowledge a proxy could be stalling because of cache >> > configuration problems, like running out fs space, or inodes and also >> > running out of memory if it has to process simultaneous requests from >> > too many clients at a time. If the problem also manifests when the >> > clients are within the same subnet, then this is unlikely to be a >> > network issue. >> >> Which hunch was that? I snipped a lot above but I couldn't find it in >> there. > > It was Alan's statement that this problem is not related to your AT&T router. > > I have to come back to this. I tried the www.google.com/nexus/ you mentioned > and noticed that the page eats up 1.3MB to load fully, before it starts > downloading a flash video. So seems to be a relatively large amount of data > that brings up this problem and this could point to tcp window scaling. It also happens on very lightweight sites, but never on squid-cache.org for some reason. >> echo 0 > /proc/sys/net/ipv4/tcp_window_scaling > > This is typically enabled, but if you notice that a connection stalls and then > later on it works fine again, it could be related to a firewall/router not > responding as it should to tcp_window_scaling. In this case disabling this > would fix the problem when traversing problematic nodes. > > If you saw no difference, this suggests that window scaling is not an issue. I just tested again and 'echo 0 > /proc/sys/net/ipv4/tcp_window_scaling' on both the client and server did not fix the stalls. > I would start with the simplest tests first, which involve isolating suspect > system components one at a time. Trying to use the same laptop-desktop > machines within the LAN, takes the router out the equation - full 1500 byte > MTU will be used by both laptop and desktop. OK I will try this as soon as I'm back in that location. Thanks a lot, Grant