From: Johannes Berg <johannes@sipsolutions.net>
To: Dani Camps <danicamps81@gmail.com>
Cc: linux-wireless@vger.kernel.org
Subject: Re: wmediumd performance penalty
Date: Mon, 01 Sep 2014 20:52:14 +0200 [thread overview]
Message-ID: <1409597534.2703.9.camel@jlt4.sipsolutions.net> (raw)
In-Reply-To: <CAD3NH5X1AYR5p8AyRyO0DFkkJUtuc_78=s6vEi-nS4UxUZfWCg@mail.gmail.com> (sfid-20140901_173813_368381_480D49AD)
On Mon, 2014-09-01 at 17:38 +0200, Dani Camps wrote:
> Dear all,
>
> I am testing a simple 1-hop mesh network over wmediumd. The PHY rate I
> have configured is 54 Mbps, and there is no loss, however the max
> throughput I get is around 14 Mbps. Without wmediumd I get around 30
> Mbps, which seems reasonable given the 54 PHY rate. As I noted above
> there is no loss probability configured in wmediumd.
>
> My impression is that the performance drop is due to the overhead of
> switching between kernel and user space in wmediumd, however it
> surprises me that the penalty is so high.
>
> Has anyone had a similar experience? Could there be a way to overcome
> this bottleneck?
What kind of system are you running on? The virtual PHY rate isn't taken
into account at all, so you should see far higher performance.
johannes
next prev parent reply other threads:[~2014-09-01 18:52 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-01 15:38 wmediumd performance penalty Dani Camps
2014-09-01 18:52 ` Johannes Berg [this message]
2014-09-02 7:31 ` Dani Camps
2014-09-02 7:55 ` Johannes Berg
2014-09-02 8:06 ` Dani Camps
2014-09-05 13:03 ` Bob Copeland
2014-09-05 14:10 ` Bob Copeland
[not found] ` <CAD3NH5UEPKw58ObsW+8dpLRFMHTEq91TSd6RAkV3H8E76Ooamw@mail.gmail.com>
2014-09-08 13:02 ` Bob Copeland
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