Return-path: Received: from he.sipsolutions.net ([78.46.109.217]:37704 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750832Ab1KXNDv (ORCPT ); Thu, 24 Nov 2011 08:03:51 -0500 Subject: Re: mac80211: AP mode - question about Tx buffered unicast frames drop timeout From: Johannes Berg To: Janusz Dziedzic Cc: linux-wireless@vger.kernel.org In-Reply-To: (sfid-20111123_193713_190763_C0FC3E1C) References: (sfid-20111123_193713_190763_C0FC3E1C) Content-Type: text/plain; charset="UTF-8" Date: Thu, 24 Nov 2011 14:03:46 +0100 Message-ID: <1322139826.5366.2.camel@jlt3.sipsolutions.net> (sfid-20111124_140355_395612_F9278CAC) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, 2011-11-23 at 19:36 +0100, Janusz Dziedzic wrote: > Hello, > > in sta_info.c I see function we call to remove expired unicast buffered frames. > > sta_info_buffer_expired() > { > ... > timeout = (sta->listen_interval * > sta->sdata->vif.bss_conf.beacon_int * > 32 / 15625) * HZ; > if (timeout < STA_TX_BUFFER_EXPIRE) > timeout = STA_TX_BUFFER_EXPIRE; > ... > } > > STA_TX_BUFFER_EXPIRE is define as 10 seconds. > Do you remember why we set this as 10 seconds in case we calculate lower value? > This "listen_interval" calculation seems to be correct. > I found this during UAPSD debuging in AP mode. I have no idea. It's probably just really old code. Now -- why would you sleep for longer than 10 seconds? That's pretty bad user experience :) But really, I don't know, and I wouldn't mind changing it either I think. johannes