From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick McHardy Date: Wed, 21 Jan 2004 00:13:04 +0000 Subject: Re: [LARTC] Fair bandwidth oversubscribing ? How with HTB ? Message-Id: <400DC410.1060201@trash.net> List-Id: References: <1187.202.49.246.211.1074629494.squirrel@webmail.igrin.co.nz> In-Reply-To: <1187.202.49.246.211.1074629494.squirrel@webmail.igrin.co.nz> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable To: lartc@vger.kernel.org Santiago J. Ruano Rinc=F3n wrote: >try HFSC, Hierarchical Fair Service Curve: > >http://trash.net/~kaber/hfsc >http://www-2.cs.cmu.edu/~hzhang/HFSC/ > >i'm going to test it in this week. > =20 > This should indeed work with HFSC if the custumer-classes have only links-haring service curves and no realtime service curves. The parent class would be limited with an upper-limit service curve. With link-sharing service curves, only the relative differences of virtual time on a level of the heirarchy are relevant, so there is no problem oversubscribing the parent class. the upper-limit service curve of the parent limits the total bandwidth, unlike the link-sharing curve it uses wall-clock time. Best regards, Patrick PS: Please let me know if you are successful. >Quoting Simon Byrnand : > > =20 > >>Hopefully someone has a suggestion on how I might do this...as I can't >>figure it out :( >> >>I need to be able to set up a group of seperate users who have a >>"bandwidth pool" they share, but also be able to limit their individual >>bandwidth as well. >> >>Example: >> >>I have 5 customers and would like to be able to provide them with a >>maximum of 256Kbit each, with a CIR of 33%. >> >>To do this, I'd like the 5 customers to share a parent group which is >>therefore limited to 426Kbit, Which is 5*256Kbit/3. >> >>The idea being that individual customers can achieve up to a maximum of >>256Kbit provided that the total group pool doesn't exceed 426Kbit, and if >>the total group pool maxes out, then each customer should get reduced >>bandwidth in fair ratios based on their individual maximum setting. >>(Currently 256Kbit for all of them, but I'd like to be able to >>differentiate them later) >> >>If all 5 were trying to fully utilize their bandwidth at the same time, >>they should get a fairly distributed 33% of their maximum - eg about >>85Kbit. >> >>The problem I can see is that both CBQ and HTB don't seem to honour >>situations where the sum of all the child rates exceeds the parent rate - >>the parent rate is ignored so the 426Kbit cap is exceeded. The HTB docs >>even explicitely say this won't work. >> >>So is there any tricky way to do this with slightly different semantics ? >>Surely there must be some way :-) I've spent many long hours studying CBQ >>and trying things out and finally came to the conclusion that CBQ alone >>just can't do it, but I was hoping HTB could, but thus far I've been >>unsuccessful here too.. >> >>Currently I'm using CBQ but I'm limited in that the individual maximum >>speeds can only equal the parent group maximum bandwidth which is workable >>for a few customers, but not very satisfactory and not flexible enough as >>I add more customers. >> >>If someone could point me in the right direction or just give me a firm >>"nope, can't be done" that would be great.... >> >>I'd also like to enable short term bursting over and above this as well, >>to improve responsiveness during downloading, say, 33% overbandwidth for 5 >>seconds, that sort of thing, but I'll cross that bridge when (if) I get to >>it...(any comments here on how effective enabling bursting is for reducing >>the dreaded unresponsiveness-during-downloads problem would be welcome >>too) >> >>Regards, >>Simon >> >>_______________________________________________ >>LARTC mailing list / LARTC@mailman.ds9a.nl >>http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/ >> >> =20 >> > > >Santiago J. Ruano Rinc=F3n > >Avatar Ltda. >ParqueSoft Popay=E1n >+57-2 8221214 > >_______________________________________________ >LARTC mailing list / LARTC@mailman.ds9a.nl >http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/ > =20 > _______________________________________________ LARTC mailing list / LARTC@mailman.ds9a.nl http://mailman.ds9a.nl/mailman/listinfo/lartc HOWTO: http://lartc.org/