From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH 1/1] TX throttling bug-fixing patch of AX88179_178A Date: Thu, 25 Jul 2013 08:11:28 -0700 Message-ID: <1374765088.23313.21.camel@edumazet-glaptop> References: <1374311809-4155-1-git-send-email-freddy@asix.com.tw> <1374512879.4990.19.camel@edumazet-glaptop> <1374518312.1635.29.camel@bwh-desktop.uk.level5networks.com> <1374518841.4990.26.camel@edumazet-glaptop> <1374522471.1635.48.camel@bwh-desktop.uk.level5networks.com> <1374559827.4990.143.camel@edumazet-glaptop> <1374729058.23313.8.camel@edumazet-glaptop> <1374750101.23313.16.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Ben Hutchings , Oliver Neukum , Grant Grundler , Freddy Xin , David Miller , netdev , linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, LKML , ASIX Louis =?UTF-8?Q?=5B=E8=98=87=E5=A8=81=E9=99=B8=5D?= , Allan Chou To: Ming Lei Return-path: In-Reply-To: Sender: linux-usb-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Thu, 2013-07-25 at 22:52 +0800, Ming Lei wrote: > Maybe need to try it with TSO enabled, in my test on ax88179_178a NIC after > applying your disabling TSO patch, tx throughput is less than 600Mbps, but rx > is close to 900Mbps. It looks like TCP stack could for this case allocate linear skbs (GFP_KERNEL context), using order-3 pages, and not adding frags on them, to avoid the skb_linearize() hazard (in GFP_ATOMIC) In case of retransmits, skb are small (one MSS) so the skb_linearize() should succeed most of the time. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html