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 E3570198005 for ; Fri, 22 Feb 2013 16:23:54 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id A90E721C092; Fri, 22 Feb 2013 16:23:46 +0000 (UTC) Received: from mail-wi0-f178.google.com (mail-wi0-f178.google.com [209.85.212.178]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id D8A9B21C003 for ; Fri, 22 Feb 2013 16:23:44 +0000 (UTC) Received: by mail-wi0-f178.google.com with SMTP id o1so950853wic.17 for ; Fri, 22 Feb 2013 08:23:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:reply-to:to:subject:date:user-agent:references :in-reply-to:mime-version:content-type:content-transfer-encoding :message-id; bh=4BJV44gTtJFrOamjIUEnmC3MnVtOabMZerUT0mHzGg0=; b=v9VZJnflyU3SWykhYg7OO+OrPXNRTTTiM7Wptbh1JGx5wLNvKPqE48UYEflEe5zORs Q2qzY08jc+VxVB627MvOG3c1xt2HFk73tJGgCsImOn/wtZHtkj6HEYV2MW51N7I8IlpU xtpz1UAYEOjVwr0Yo8PWEXYi/RuXlo61Y5fF1+VjVPNH3P8oylRzVHX5Flz2xxCmVqAb 1zzY9eWfPeQNlnK9fieeXzaTsx1OI17pto4uElz0MOAtfBA0sSSXlaWAPKCoqDrAnC4Q R0+XaNEbR23m3MKoc7RnLD2X/GnQJTy9NbCVq72Xu6BZOacG2PN19b6RD6Aev9LaQ2yO ohQg== X-Received: by 10.180.109.82 with SMTP id hq18mr4622412wib.0.1361550218185; Fri, 22 Feb 2013 08:23:38 -0800 (PST) Received: from dell_xps.localnet (230.3.169.217.in-addr.arpa. [217.169.3.230]) by mx.google.com with ESMTPS id fg6sm4488490wib.10.2013.02.22.08.23.36 (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 22 Feb 2013 08:23:37 -0800 (PST) From: Mick To: gentoo-user@lists.gentoo.org Subject: Re: [gentoo-user] Slow local network - how to debug? Date: Fri, 22 Feb 2013 16:22:58 +0000 User-Agent: KMail/1.13.7 (Linux/3.6.11-gentoo; KDE/4.9.5; x86_64; ; ) References: <1361543782.23748.1@numa-i> In-Reply-To: <1361543782.23748.1@numa-i> 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 Content-Type: multipart/signed; boundary="nextPart1425115.OQX9EzEgcR"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201302221623.12077.michaelkintzios@gmail.com> X-Archives-Salt: 69433972-1604-46ad-a5bb-308ec5b424bd X-Archives-Hash: 330113d0a1a07f4acf0beaa995acceec --nextPart1425115.OQX9EzEgcR Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Friday 22 Feb 2013 14:36:22 Helmut Jarausch wrote: > On 02/22/2013 02:55:07 PM, Mick wrote: > > On Friday 22 Feb 2013 08:04:38 Helmut Jarausch wrote: > > > When copying data from one machine to the other one I see varying > > > speeds from only 0.5 Mbits/s up to > > > more than 20 Mbits/s. I have no idea why it is so slow some times. > > > There are no other wireless devices nearby. > >=20 > > Where do you see these transfer speeds? On the wired machine, or on > > the > > wireless machine? > >=20 > > What do you use to check the transfer speed? >=20 > One tool is ttcp which is very similar to netcat and this concerns me > most. > The other tool is a remote webserver for measure internet speed I suggest that you troubleshoot speeds across your LAN first, before you lo= ok=20 at connections across the Internet which tend to be less consistent. > > Do the speeds go up when you used a Cat5e cable at full duplex? >=20 > The PC which is wired doesn't have those problems since I can transmit > data from > my remote office machine at the highest possble rate which is specified > by my > internet provider. What I'm saying is: When you connect BOTH machines to your router with cat= 5e=20 cables does the performance improve? I didn't know that you were using ttcp and was trying to eliminate other=20 bottlenecks, e.g. storage caching, or drive controller problems if you were= =20 transferring a file. > > Have you scanned for access points to be absolutely sure that there > > are no > > other wireless devices, or APs? > >=20 > > Do you use encryption? >=20 > Yes, but since I do get optimal performance "some time" I don't think > this matters. Right, inconsistent performance could be due to interference, rather than=20 someone free-riding your open WiFi network. > > What frequency and channel are you on and have you tried to change > > channel/frequency? (some domestic devices like cordless phones, > > wireless > > earphones, bluetooth, microwaves, perimeter sensors, etc. can cause > > co-channel > > and adjacent channel interference and/or force sharing of the > > bandwidth). This may eliminate interference problems, but only if concentrated on a=20 particular frequency. Broadband transmissions will still interfere. You could try moving your laptop around the premises to see if you can spot= =20 some device/appliance that may be causing this. > > Are both machines and the router's LAN on the same MTU? >=20 > Sorry, what's "MTU" ? http://en.wikipedia.org/wiki/Maximum_transmission_unit I was trying to see if there is a mismatch which may cause excessive=20 fragmentation. =2D-=20 Regards, Mick --nextPart1425115.OQX9EzEgcR Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (GNU/Linux) iEYEABECAAYFAlEnm3AACgkQVTDTR3kpaLZhPgCgu+Kq7M347pgrvOrsw/GXLFxy ZPMAn2jkPbGFAxeNkJwUb+iL40xchwci =IJZh -----END PGP SIGNATURE----- --nextPart1425115.OQX9EzEgcR--