From: Kalle Valo <kalle.valo@iki.fi>
To: Lennert Buytenhek <buytenh@wantstofly.org>
Cc: linux-wireless@vger.kernel.org
Subject: Re: infinite transmit buffering issue in 2.6.32 mac80211
Date: Tue, 05 Jan 2010 20:29:00 +0200 [thread overview]
Message-ID: <87eim4v21f.fsf@purkki.valot.fi> (raw)
In-Reply-To: <20100105083803.GP1735@mail.wantstofly.org> (Lennert Buytenhek's message of "Tue\, 5 Jan 2010 09\:38\:03 +0100")
Lennert Buytenhek <buytenh@wantstofly.org> writes:
> Hi!
Hello,
> Since "mac80211: remove master netdev", mac80211 no longer propagates
> TX queue full status (ieee80211_stop_queue et al) up. While the
> underlying hardware's TX queue is stopped, mac80211 buffers frames
> internally (in ieee80211_tx), but there's no upper limit on the number
> of frames it will buffer, leading to badness when there is heavy TX
> traffic on the wireless interface:
We have noticed very strange throughput degration both with wl1251 and
wl1271. With 2.6.28 both drivers were able to achieve 10 Mbit/s
throughput over TCP, but with 2.6.32 (and almost the same drivers) we
get less than 4 Mbit/s. Because we see it both with wl1251 and wl1271,
we are starting to suspect that it's a problem in mac80211.
We haven't started analysing this yet, but I'm hoping someone from our
team to start it soon. I have no idea if our problem is related to the
problem Lennert reports or not, but we will definitely try Johannes'
patch and see if it helps.
--
Kalle Valo
prev parent reply other threads:[~2010-01-05 18:29 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-05 8:38 infinite transmit buffering issue in 2.6.32 mac80211 Lennert Buytenhek
2010-01-05 17:01 ` Luis R. Rodriguez
2010-01-05 17:20 ` Lennert Buytenhek
2010-01-05 18:29 ` Kalle Valo [this message]
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