Return-path: Received: from mail-io0-f171.google.com ([209.85.223.171]:35110 "EHLO mail-io0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752199AbcBGEVq (ORCPT ); Sat, 6 Feb 2016 23:21:46 -0500 Received: by mail-io0-f171.google.com with SMTP id d63so166594597ioj.2 for ; Sat, 06 Feb 2016 20:21:46 -0800 (PST) MIME-Version: 1.0 Date: Sat, 6 Feb 2016 23:21:45 -0500 Message-ID: (sfid-20160207_052151_347889_33C93C93) Subject: Monitor interface TX performance boost From: Nikolay Martynov To: linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi. I'm seeing strange behavior on my intel 6300 card. If I measure TX performance just after boot (iperf in tcp mode), I get this: [ 3] 0.0-10.1 sec 11.2 MBytes 9.32 Mbits/sec But if create and enable monitor interface (with command like 'sudo iw phy phy0 interface add moni0 type monitor && sudo ifconfig moni0 up') I get this: [ 3] 0.0-10.1 sec 34.8 MBytes 29.0 Mbits/sec That's about three times boost in throughput by just creating an interface (without even using it). Doing 'ifconfig moni0 down' bring performance back to 10Mbits range. Experiments are done with laptop being ~5m from router and not moving. These results are repeatable, i.e. not caused by random things like other stations transmitting, or channel being busy. Is this something expected? Is there any reason performance can be as good without monitor interface existing? Thanks! -- Martynov Nikolay. Email: mar.kolya@gmail.com