Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3161C43382 for ; Wed, 26 Sep 2018 18:27:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 912312152F for ; Wed, 26 Sep 2018 18:27:10 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 912312152F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sipsolutions.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-wireless-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727399AbeI0AlW (ORCPT ); Wed, 26 Sep 2018 20:41:22 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:44988 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727235AbeI0AlW (ORCPT ); Wed, 26 Sep 2018 20:41:22 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.91) (envelope-from ) id 1g5EWh-0002NU-98; Wed, 26 Sep 2018 20:27:07 +0200 Message-ID: <1537986415.28767.17.camel@sipsolutions.net> Subject: Re: How many null-data probes on connection loss? From: Johannes Berg To: Ben Greear , "linux-wireless@vger.kernel.org" Date: Wed, 26 Sep 2018 20:26:55 +0200 In-Reply-To: References: <9a1447d9-9a61-dc2d-0101-33c6bdeb946f@candelatech.com> <1537951137.28767.5.camel@sipsolutions.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 (3.26.6-1.fc27) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Wed, 2018-09-26 at 11:04 -0700, Ben Greear wrote: > I have been running with mac80211/mlme.c's max_nullfunc_tries set to 5 for many years. > Long ago it helped with connectivity issues with lots of vdevs and and/orloaded APs > if I recall correctly. That's different, that's the number of distinct frames mac80211 will send. I thought you were asking about *retries*. > In fact, I see 62 frames captured on air all with the same sequence number > in the test I just did, and subsequent frames with the next seq-no are sent > immediately after the first one. The frames are all right after each other, so > I guess this is probably firmware doing lots of HW retransmits and then *also* > doing software retransmits in the firmware (my reading of mlme.c indicates it should > only probe every 500ms). Yes. > I think I'll start by making sure the firmware does not do software retransmits > for frames from the driver (self-gen frames are OK to be retransmitted I guess). You do want it to be doing retries for frames from the driver, since you want it to recover from temporary collisions with a microwave and whatnot ... just not *that many*, I guess. johannes