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From: Eric Dumazet <eric.dumazet@gmail.com>
To: Dave Taht <dave.taht@gmail.com>
Cc: Gabor Juhos <juhosg@openwrt.org>, bloat <bloat@lists.bufferbloat.net>
Subject: Re: [Bloat] tiny monsters: multicast packets
Date: Sun, 29 May 2011 21:14:36 +0200	[thread overview]
Message-ID: <1306696476.30021.21.camel@edumazet-laptop> (raw)
In-Reply-To: <BANLkTi=mhS+u-NkuFS2fM5WDJR_jeO4KWA@mail.gmail.com>

Le dimanche 29 mai 2011 à 11:40 -0600, Dave Taht a écrit :

>         
> 
> perf-top does not appear to have been ported to openwrt, and as cool
> as it is, I do not know if the related performance counters exist for
> mips.
> 
> it would be darn useful though.
> 
> All I know at the moment is that sirq is at 99% at the given
> workload, 
> according busybox's top.
> 
> http://www.bufferbloat.net/attachments/download/33/routertest.png
> 
> It is mildly early to point at the driver as being the issue - it
> could be the switch or something else entirely. Would iptables or qos
> rules show up in sirq?
> 

Yes, about all this stuff is run in softirq. QOS can be a problem if
high resolution kernel time services are expensive on this platform.

You could try a raw routing stuff, with no QOS / iptables, just to see
how much packets can be received/sent by this unit.

And if it stills sucks, just do an input test only, dropping packets
immediately with "iptables -I INPUT -i name -j DROP" (to check how many
packets/second can be received by the driver)




  parent reply	other threads:[~2011-05-29 18:58 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-05-29 13:23 Dave Taht
2011-05-29 14:10 ` Jonathan Morton
2011-05-29 15:10   ` Dave Taht
2011-05-29 15:33     ` Juliusz Chroboczek
2011-05-29 15:44       ` Dave Taht
2011-05-29 15:51         ` Juliusz Chroboczek
2011-05-29 16:07           ` Dave Taht
2011-05-29 16:07             ` Dave Taht
2011-05-29 16:53               ` Dave Taht
2011-05-29 16:33             ` Eric Dumazet
2011-05-29 17:02               ` Dave Taht
2011-05-29 17:17                 ` Eric Dumazet
2011-05-29 17:40                   ` Dave Taht
2011-05-29 17:47                     ` Jonathan Morton
2011-05-29 19:14                     ` Eric Dumazet [this message]
2011-05-29 15:21   ` Juliusz Chroboczek
2011-05-29 15:57     ` Dave Taht
2011-05-31 14:58       ` Jim Gettys

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