From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120] helo=us-smtp-1.mimecast.com) by bombadil.infradead.org with esmtps (Exim 4.92.2 #3 (Red Hat Linux)) id 1iAWkI-0007nV-D6 for ath10k@lists.infradead.org; Wed, 18 Sep 2019 09:59:36 +0000 Received: by mail-ed1-f71.google.com with SMTP id d7so4036149edp.23 for ; Wed, 18 Sep 2019 02:59:31 -0700 (PDT) From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= Subject: Re: [PATCH V2 3/4] mac80211: fix low throughput in multi-clients situation In-Reply-To: <1568800033-17297-3-git-send-email-yiboz@codeaurora.org> References: <1568800033-17297-1-git-send-email-yiboz@codeaurora.org> <1568800033-17297-3-git-send-email-yiboz@codeaurora.org> Date: Wed, 18 Sep 2019 11:59:28 +0200 Message-ID: <874l19j56n.fsf@toke.dk> MIME-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Yibo Zhao , ath10k@lists.infradead.org Cc: linux-wireless@vger.kernel.org Yibo Zhao writes: > Not long after the start of multi-clients test, not a single station is > an eligible candidate for transmission since global virtual time(g_vt) is > smaller than the virtual airtime(s_vt) of all the stations. As a result, > the Tx has been blocked and throughput is quite low. > > This may mainly due to sync mechanism and accumulative deviation from the > devision calculation of g_vt. > > For example: > Suppose we have 50 clients in first round. > Round 1: > STA weight Tx_time_round wt_sum s_vt g_vt valid_for_next_Tx > . . . . . > . . . . . > . . . . . > > After this round, all the stations are not valid for next transmission due > to accumulative deviation. > > And if we add a new #51, > Round 2: > STA weight Tx_time_round wt_sum s_vt g_vt valid_for_next_Tx > . . . . . > . . . . . > . . . . . > > Sync is done by: > max(g_vt of last round - grace period, s_vt) > and s_vt of #51 = max(2000 - 500, 0) + 1024 = 2524, and it is more than the > final g_vt of this round. > > After this round, no more station is valid for transmission. I'm not sure I understand this. Was there supposed to be numbers in those tables above? -Toke _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k