From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sipsolutions.net (s3.sipsolutions.net [IPv6:2a01:4f8:191:4433::2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 884613B29E for ; Fri, 4 Oct 2019 08:34:43 -0400 (EDT) Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.92.2) (envelope-from ) id 1iGMnB-000819-Sd; Fri, 04 Oct 2019 14:34:42 +0200 Message-ID: <0dbf438d7e176c85164b8568a98f0d6e98292152.camel@sipsolutions.net> From: Johannes Berg To: Kan Yan Cc: linux-wireless@vger.kernel.org, make-wifi-fast@lists.bufferbloat.net, toke@redhat.com, nbd@nbd.name, yiboz@codeaurora.org Date: Fri, 04 Oct 2019 14:34:41 +0200 In-Reply-To: <20191004062151.131405-2-kyan@google.com> (sfid-20191004_082219_852781_215A08B7) References: <20191004062151.131405-1-kyan@google.com> <20191004062151.131405-2-kyan@google.com> (sfid-20191004_082219_852781_215A08B7) Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [Make-wifi-fast] [PATCH 1/2] mac80211: Implement Airtime-based Queue Limit (AQL) X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 04 Oct 2019 12:34:43 -0000 On Thu, 2019-10-03 at 23:21 -0700, Kan Yan wrote: > > +/* The firmware's transmit queue size limit in airtime */ > +#define IEEE80211_DEFAULT_AQL_INTERFACE_LIMIT 24000 I'm not sure I understand this completely, but IMHO rewording it to be like a "NIC limit" would be better. However, I'm not sure it *shouldn't* actually be per interface (i.e. moving from local->aql_total_pending_airtime to sdata->aql_total_pending_airtime because you could have multiple channels etc. involved and then using a single airtime limit across two interfaces that are actually on two different channels (e.g. 2.4 and 5 GHz) doesn't make that much sense. Actually, it does make some sense as long as the NIC is actually channel-hopping ... but that's in the process of changing now, there's going to be hardware really soon (or perhaps already exists) that has real dual-band capabilities... Maybe we can live with this now, but we'd probably expect to change this really soon. johannes