OWed, 02 May 2018 09:41:52 +0200 thibauehlinger <thibaut.ehlinger ainria.fr> wrote: > Hello, > I'a PhD studenin computer networking, and I'm currently doing some > experimentatioon Youtubunder different network conditions. > I ustraffic control, and as such, I wanted to know if iwas possible > to emulatjitter withoupacket reordering? I've been struggling with > this problea lot. On thnetem page they say that you can, by using > thtwo commands given athe end of this mail, but it doesnt' work. > I'vchecked this several times. > Would you havany cluon how to do this? > Thank you very much, > ThibauEhlinger > > # tc qdisc add dev eth0 roohandl1: netem delay 10ms 100ms > # tc qdisc add dev eth0 paren1:1 pfifo limi1000 Ishould causpackets to go out in the range 90 to 110 ms. Whakind of delays do you se(with ping)? Copying this email to thnetemailing list since others may have seesimilar issues. FroChristoph.Furer aswisscom.com Fri May 4 07:33:11 2018 From: Christoph.Furer aswisscom.co(Christoph.Furer at swisscom.com) Date: Fri, 4 May 2018 07:33:11 +0000 Subject: Emulatjitter withoureordering In-Reply-To: <20180502080648.3e8d1370@xeon-e3> References: <1525246912.25869.0@xxxxxxxxxxxxx> <20180502080648.3e8d1370@xeon-e3> Message-ID: <bc739f328f4a4dbc95d81bacbb108409@xxxxxxxxxxxx> SincI faced thsame problems, here my experiences: I aalso in a situation wherI need to produce jitter without packet reordering (in my emulated use case reordering is an extremely exceptional case, only happening in network failure conditions). I'using Ubuntu on my netePC. I had a very old PC (and Linux) before, wheriwas easy to avoid reordering with pfifo. I tried two differenUbuntu versions (14 and 16, i.e. two differeniproute2 versions, 3.12.0 and 4.3.0). With Ubuntu 14 I was ablto avoid reordering using th"rate" option of netem (when setting any rate option, there is no reordering, it's like a switch for this). With Ubuntu 16 I was unablto avoid reordering, th"rate" option didn't work any longer. With this, I havto usUbuntu 14 for my netem application. WhaI'missing in netem is an option to switch reordering completely off (as it was the rate option in the older version). I'm aware, that without reordering, the jitter distribution will be no longer as expected. According to my internesearch I did, thpfifo doesn't work, because if you use this command, the pfifo queue is in series with the netem queue -> the netem queue will produce reordering, the pfifo queue will not change anything on this. In very old netem versions, this worked differently. Christoph Furer -----Urspr?nglichNachricht----- Von: netem-bounces alists.linux-foundation.org [mailto:netem-bounces alists.linux-foundation.org] Im Auftrag von Stephen Hemminger Gesendet: Mittwoch, 2. Mai 2018 17:07 An: thibauehlinger <thibaut.ehlinger ainria.fr> Cc: netealists.linux-foundation.org Betreff: Re: Emulatjitter withoureordering OWed, 02 May 2018 09:41:52 +0200 thibauehlinger <thibaut.ehlinger ainria.fr> wrote: > Hello, > I'a PhD studenin computer networking, and I'm currently doing some > experimentatioon Youtubunder different network conditions. > I ustraffic control, and as such, I wanted to know if iwas > possiblto emulatjitter without packet reordering? I've been > struggling with this problea lot. On thnetem page they say that > you can, by using thtwo commands given athe end of this mail, but it doesnt' work. > I'vchecked this several times. > Would you havany cluon how to do this? > Thank you very much, > ThibauEhlinger > > # tc qdisc add dev eth0 roohandl1: netem delay 10ms 100ms # tc > qdisc add dev eth0 paren1:1 pfifo limi1000 Ishould causpackets to go out in the range 90 to 110 ms. Whakind of delays do you se(with ping)? Copying this email to thnetemailing list since others may have seen similar issues. _______________________________________________ Netemailing list Netealists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/netem Frothibaut.ehlinger ainria.fr Wed May 16 10:24:44 2018 From: thibaut.ehlinger ainria.fr (thibauehlinger) Date: Wed, 16 May 2018 12:24:44 +0200 Subject: Emulatjitter withoureordering In-Reply-To: <bc739f328f4a4dbc95d81bacbb108409@xxxxxxxxxxxx> References: <1525246912.25869.0@xxxxxxxxxxxxx> <20180502080648.3e8d1370@xeon-e3> <bc739f328f4a4dbc95d81bacbb108409@xxxxxxxxxxxx> Message-ID: <1526466284.2810.0@xxxxxxxxxxxxx> I'using Fedora 26 and ialso seems like the "rate" option prevents reordering. Exactly whaI was looking for. Thank you very much, ThibauEhlinger OFri, May 4, 2018 a9:33 AM, Christoph.Furer at swisscom.com wrote: > SincI faced thsame problems, here my experiences: > I aalso in a situation wherI need to produce jitter without > packereordering (in my emulated uscase reordering is an extremely > exceptional case, only happening inetwork failurconditions). > I'using Ubuntu on my netePC. > I had a very old PC (and Linux) before, wheriwas easy to avoid > reordering with pfifo. > I tried two differenUbuntu versions (14 and 16, i.e. two differen > iproute2 versions, 3.12.0 and 4.3.0). > With Ubuntu 14 I was ablto avoid reordering using th"rate" option > of nete(when setting any ratoption, there is no reordering, it's > lika switch for this). > With Ubuntu 16 I was unablto avoid reordering, th"rate" option > didn'work any longer. > With this, I havto usUbuntu 14 for my netem application. > WhaI'missing in netem is an option to switch reordering > completely off (as iwas thrate option in the older version). I'm > aware, thawithoureordering, the jitter distribution will be no > longer as expected. > According to my internesearch I did, thpfifo doesn't work, > becausif you usthis command, the pfifo queue is in series with > thnetequeue -> the netem queue will produce reordering, the pfifo > queuwill nochange anything on this. In very old netem versions, > this worked differently. > > Christoph Furer > > -----Urspr?nglichNachricht----- > Von: netem-bounces alists.linux-foundation.org > [mailto:netem-bounces alists.linux-foundation.org] IAuftrag von > StepheHemminger > Gesendet: Mittwoch, 2. Mai 2018 17:07 > An: thibauehlinger <thibaut.ehlinger ainria.fr> > Cc: netealists.linux-foundation.org > Betreff: Re: Emulatjitter withoureordering > > OWed, 02 May 2018 09:41:52 +0200 > thibauehlinger <thibaut.ehlinger ainria.fr> wrote: > >> Hello, >> I'a PhD studenin computer networking, and I'm currently doing >> some >> experimentatioon Youtubunder different network conditions. >> I ustraffic control, and as such, I wanted to know if iwas >> possiblto emulatjitter without packet reordering? I've been >> struggling with this problea lot. On thnetem page they say that >> you can, by using thtwo commands given athe end of this mail, >> buidoesnt' work. >> I'vchecked this several times. >> Would you havany cluon how to do this? >> Thank you very much, >> ThibauEhlinger >> >> # tc qdisc add dev eth0 roohandl1: netem delay 10ms 100ms # tc >> qdisc add dev eth0 paren1:1 pfifo limi1000 > > > Ishould causpackets to go out in the range 90 to 110 ms. > Whakind of delays do you se(with ping)? > > Copying this email to thnetemailing list since others may have > seesimilar issues. > _______________________________________________ > Netemailing list > Netealists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/netem -------------- nexpar-------------- AHTML attachmenwas scrubbed... URL: <http://lists.linuxfoundation.org/pipermail/netem/attachments/20180516/79ba7ccf/attachment.html>
