From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Juliusz Chroboczek <jch@pps.univ-paris-diderot.fr>
Cc: Baptiste Jonglez <baptiste.jonglez@ens-lyon.fr>,
babel-users@lists.alioth.debian.org, bloat@lists.bufferbloat.net
Subject: Re: [Bloat] [Babel-users] RTT stability inside a GRE tunnel
Date: Tue, 2 Jul 2013 06:48:14 +0200 (CEST) [thread overview]
Message-ID: <alpine.DEB.2.00.1307020640190.10894@uplift.swm.pp.se> (raw)
In-Reply-To: <871u7hesmm.wl%jch@pps.univ-paris-diderot.fr>
On Tue, 2 Jul 2013, Juliusz Chroboczek wrote:
> Anybody seen anything similar?
I don't know if this is the cause, but older gear from Extreme Networks
(their end-of-90ties and beginning of 2000s), will do ICMP in slow-path
when routing (even packets going through the device) and "everything else"
in fast-path. This could cause latency spikes and PDV approximately
similar to what's seen in the picture.
The seen behaviour could also perhaps be caused by per-packet QoS settings
in the path, where ICMP might have lower priority than GRE. I don't think
this explanation is likely though.
--
Mikael Abrahamsson email: swmike@swm.pp.se
next prev parent reply other threads:[~2013-07-02 4:48 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20130701164607.GB12090@ens-lyon.fr>
2013-07-01 23:58 ` [Bloat] Fwd: " Juliusz Chroboczek
2013-07-02 0:02 ` [Bloat] " Juliusz Chroboczek
2013-07-02 4:48 ` Mikael Abrahamsson [this message]
2013-07-02 11:08 ` Baptiste Jonglez
2013-07-02 11:27 ` Mikael Abrahamsson
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