From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= Date: Sat, 11 Jun 2011 20:05:58 +0200 Subject: Can iperf work with no qos? (TCP mode) In-Reply-To: <20110611195721.735dcf4c@maggie> References: <20110611195721.735dcf4c@maggie> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: =?UTF-8?Q?Michael_B=C3=BCsch?= Cc: b43-dev , linux-wireless@vger.kernel.org W dniu 11 czerwca 2011 19:57 u?ytkownik Michael B?sch napisa?: > On Sat, 11 Jun 2011 19:47:31 +0200 > Rafa? Mi?ecki wrote: > >> I can not get any results when trying to use iperf in TCP mode with >> driver not supporting qos. >> >> Is this expected? Does iperf fill connection with so many packets, >> it's not possible to get response from the iperf receiver? Should not >> Linux somehow schedule packet to allow bi-direction communication, >> even on really filled connection? > > iperf will only fill the best effort queue. At least that's what it did > last time when I looked into the code. > You can verify that with b43's ring statistics. It's BE queue we create for qos=0 in b43: else q = dev->pio.tx_queue_AC_BE; so this should not limit iperf As another test, I've just tried dma mode with qos=0. iperf was fine. So now we know iperf does not need multiple queues. It seems that: GOOD: b43 & dma & no qos BAD: b43 & pio & no qos In the second case connection is started (I can see that from "iperf -s" on my receiving machine), but it seems sender does not receive any confirmations. -- Rafa?