From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [RFC PATCH v2 03/14] xsk: add umem fill queue support and mmap Date: Thu, 12 Apr 2018 17:04:55 +0300 Message-ID: <20180412170110-mutt-send-email-mst@kernel.org> References: <20180327165919.17933-1-bjorn.topel@gmail.com> <20180327165919.17933-4-bjorn.topel@gmail.com> <20180412050542-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , "Duyck, Alexander H" , "alexander.duyck@gmail.com" , "john.fastabend@gmail.com" , "ast@fb.com" , "brouer@redhat.com" , "willemdebruijn.kernel@gmail.com" , "daniel@iogearbox.net" , "netdev@vger.kernel.org" , "michael.lundkvist@ericsson.com" , "Brandeburg, Jesse" , "Singhai, Anjali" , "Zhang, Qi Z" , "ravineet.singh@ericsson.com" To: "Karlsson, Magnus" Return-path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:59402 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752095AbeDLOFA (ORCPT ); Thu, 12 Apr 2018 10:05:00 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Thu, Apr 12, 2018 at 07:38:25AM +0000, Karlsson, Magnus wrote: > I think you are definitely right in that there are ways in which > we can improve performance here. That said, the current queue > performs slightly better than the previous one we had that was > more or less a copy of one of your first virtio 1.1 proposals > from little over a year ago. It had bidirectional queues and a > valid flag in the descriptor itself. The reason we abandoned this > was not poor performance (it was good), but a need to go to > unidirectional queues. Maybe I should have only changed that > aspect and kept the valid flag. Is there a summary about unidirectional queues anywhere? I'm curious to know whether there are any lessons here to be learned for virtio or ptr_ring. -- MST