Date: Fri, 31 Aug 2001 10:12:43 -0700 (PDT) From: Luigi Rizzo <rizzo@aciri.org> To: patrick@mip.co.za (Patrick O'Reilly) Cc: rizzo@aciri.org, freebsd-ipfw@FreeBSD.ORG Subject: Re: DUMMYNET Message-ID: <200108311712.f7VHChv42153@iguana.aciri.org> In-Reply-To: <NDBBIMKICMDGDMNOOCAIOEGLDGAA.patrick@mip.co.za> from "Patrick O'Reilly" at "Aug 31, 2001 9: 3:15 am"
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> Luigi, > > I'll test further. I did use 'ipfw pipe list' to verify the 'bw' setting, > and it was '1bit/s'. Yet, there were packets passing through the pipeline > at the rate of two or three tcp setup packets per second, which must be at that is too much, sounds like these packets were not going through the pipe at all (maybe a different 'setup' rule was matching them ?). I tried yesterday with pings through a 100bit/s pipe and the RTTs were in the order of ~13 seconds, so i am pretty sure that the timing is correct even at low speeds. cheers luigi > the very least 100bit/s, perhaps more. > > Anyway Luigi, I appreciate your time in responding, and I really don't want > you to waste any time on this issue which is so close to the edges of > sanity! > > Thanks, > Patrick. > > -----Original Message----- > From: Luigi Rizzo [mailto:rizzo@aciri.org] > Sent: 30 August 2001 19:21 > To: Patrick O'Reilly > Cc: rizzo@aciri.org; freebsd-ipfw@FreeBSD.ORG > Subject: Re: DUMMYNET > > > > Agreed - the solution suggested is the way to go. The question re 1bit/s > is > > that according to my observation it did NOT slow down to that rate, but > > continued to allow traffic at a much higher rate, though it did not appear > > to be UNLIMITED. > > when i tried it, it really worked as low as 1bit/s. Have you checked > with "ipfw pipe show" to make sure that the speed associated to > the pipe was really 1bit/s and not higher ? > > cheers > luigi > > > This is obviously a moot point as no-one in their right mind (I clearly am > > excluded from that group :) would be using DUMMYNET to actually apply a > > bandwidth limit of 1bit/s. But, it begs the question: What is the lowest > > bandwidth which can be specified which DUMMYNET will be able to implement > > accurately? > > > > Anyhow - I don't want to waste any time on this now as an intelligent and > > elegant (and somewhat obvious) solution to my requirement has been given, > > and DUMMYNET has very successfully managed bandwidth down to as low as > > 8kbit/s in my experience. > > > > Thanks to all for your input! > > > > Patrick. > > > > -----Original Message----- > > From: Luigi Rizzo [mailto:rizzo@aciri.org] > > Sent: 29 August 2001 21:18 > > To: Patrick O'Reilly > > Cc: freebsd-ipfw@FreeBSD.ORG > > Subject: Re: DUMMYNET > > > > > > > Now I have changed cron to simply change the pipe config on the fly > :"ipfw > > > pipe x config bw 32Kbit/s" to open it up, and :"ipfw pipe x config bw > > > 1bit/s" to shut it down. This way my counter values continue to > > > accumulate - GREAT! > > > > > > The problem is that the pipe seems to dislike the idea of running at 1 > bit > > > per second. Obviously this is rather extreme! Any suggestions on how I > > > > as someone suggested, adding a rule in front of the pipe solves your > > problem more elegantly. But what is wrong with the pipe at 1 bit/s > > other than leaving packets go out albeit veeeeeery slooooooowly ? > > > > BTW changing HZ has no observable effect as such low speeds. > > > > cheers > > luigi > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-ipfw" in the body of the message
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