From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Thomas SPECK" Date: Thu, 08 Aug 2002 11:03:48 +0000 Subject: Re: [LARTC] pb with ingress policy Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: lartc@vger.kernel.org >Messsage du 07/08/2002 16:42 >De : Patrick McHardy >A : Thomas SPECK >Copie =E0 : >Objet : Re: [LARTC] pb with ingress policy =20 > > Hi. >=20 > Thomas SPECK wrote: >=20 > > Hi ! > >=20 > > I have a single host which is connected via an 512kbit ADSL link to the= net. I quite often use some realaudio application that uses some bandwidth= and I want to avoid other traffic to scale that bandwidth down. So I used = some classes (with htb) on imq0 device and applied some filters and it seem= s to work in most cases. However, there are some sites with which download = is interrupted if bandwidth is limited. I tried to trace it down and did so= me simple test: > >=20 > > modprobe imq numdevs=3D1 > > tc qdisc add dev imq0 root handle 1: htb default 10 > > tc class add dev imq0 parent 1: classid 1:10 htb rate 60kbit ceil 512kb= it burst 15k > > tc qdisc add dev imq0 parent 1:10 handle 10: sfq perturb 10 > > iptables -t mangle -A PREROUTING -i ppp0 -j IMQ --todev 0 > > ip li set imq0 up > >=20 > > So now all traffic is limited to 60kbit. If I use some particular site = for downloading (with wget) I observe the following with tcpdump: > > At the beginning there is a huge burst (wget indicating something like = 45 kbps) than speed decreases dramatically and achieves some equilibrium ar= ound 60kbit. Then for some reason after about 15 seconds my host sends FIN = to the other site. Why ? ;-) >=20 >=20 > Hard to tell without seeing any data. Can you capture the session with=20 > tcpdump and put it online somewhere (or send it via email off-list) ? Unfortunately the site is down now, so I can't do any tests anymore. I trie= d to find some other site but without succces :(=20 I could reproduce it with realplayer but I am not sure if it is not realpla= yer shutting down and causing the FIN or the FIN causing realplayer to shut= down ... (BTW I am not sure with wget as well, so could that all be an app= lication problem ?) If you would like to see the dump anyway, please let me know. -- Thomas _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/