From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: Receive offloads, small RCVBUF and zero TCP window Date: Mon, 28 Nov 2016 15:54:59 -0500 (EST) Message-ID: <20161128.155459.1527519991492144879.davem@davemloft.net> References: <2080597.A38JFJZ1AD@zbook> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: alexandre.sidorenko@hpe.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:41794 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753005AbcK1UzB (ORCPT ); Mon, 28 Nov 2016 15:55:01 -0500 In-Reply-To: <2080597.A38JFJZ1AD@zbook> Sender: netdev-owner@vger.kernel.org List-ID: From: Alex Sidorenko Date: Mon, 28 Nov 2016 15:49:26 -0500 > Now the question is whether is is OK to have icsk->icsk_ack.rcv_mss > larger than MTU. It absolutely is not OK. If VMWare wants to receive large frames for batching purposes it must use GRO or similar to achieve that, not just send vanilla frames into the stack which are larger than the device MTU.