From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751443AbcAXJPM (ORCPT ); Sun, 24 Jan 2016 04:15:12 -0500 Received: from plane.gmane.org ([80.91.229.3]:58534 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751045AbcAXJPH (ORCPT ); Sun, 24 Jan 2016 04:15:07 -0500 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: Mike Rapoport Subject: Re: [PATCH V2 0/3] basic busy polling support for =?utf-8?b?dmhvc3RfbmV0?= Date: Sun, 24 Jan 2016 09:00:01 +0000 (UTC) Message-ID: References: <1448951985-12385-1-git-send-email-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: sea.gmane.org User-Agent: Loom/3.14 (http://gmane.org/) X-Loom-IP: 195.110.40.7 (Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:43.0) Gecko/20100101 Firefox/43.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jason, > Jason Wang redhat.com> writes: > > Hi all: > > This series tries to add basic busy polling for vhost net. The idea is > simple: at the end of tx/rx processing, busy polling for new tx added > descriptor and rx receive socket for a while. There were several conciens Michael raised on the Razya's attempt to add polling to vhost-net ([1], [2]). Some of them seem relevant for these patches as well: - What happens in overcommit scenarios? - Have you checked the effect of polling on some macro benchmarks? > The maximum number of time (in us) could be spent on busy polling was > specified ioctl. Although ioctl is definitely more appropriate interface to allow user to tune polling, it's still not clear for me how *end user* will interact with it and how easy it would be for him/her. [1] http://thread.gmane.org/gmane.linux.kernel/1765593 [2] http://thread.gmane.org/gmane.comp.emulators.kvm.devel/131343 -- Sincerely yours, Mike.