From mboxrd@z Thu Jan 1 00:00:00 1970 From: annie li Subject: Re: [PATCH 0/4] Implement persistent grant in xen-netfront/netback Date: Sat, 17 Nov 2012 12:39:21 +0800 Message-ID: <50A714F9.4040206@oracle.com> References: <1352962987-541-1-git-send-email-annie.li@oracle.com> <1353059821.3499.190.camel@zakaz.uk.xensource.com> <50A6255C.10108@oracle.com> <1353066382.3499.227.camel@zakaz.uk.xensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1353066382.3499.227.camel@zakaz.uk.xensource.com> Sender: netdev-owner@vger.kernel.org To: Ian Campbell Cc: "xen-devel@lists.xensource.com" , "netdev@vger.kernel.org" , "konrad.wilk@oracle.com" List-Id: xen-devel@lists.xenproject.org On 2012-11-16 19:46, Ian Campbell wrote: > > It seems like having netfront simply allocate itself a pool of grant > references which it reuses would give equivalent benefits whilst being a > smaller patch, with no protocol change and avoiding double copying. In > fact by avoiding the double copy I'd expect it to be even better. > > OK, I can try this implementation. And I'd better to compare the performance between double copy and this implementation to see how much grant lock affects grant copy too. > I think you need to measure both dom0->domU and domU->dom0 to get the > full picture since AIUI netperf sends the bulk data in only one > direction with just ACKs coming back the other way. > Yes. My environment does not meet requirement of more VMs, I would do more thorough test after Konrad setups the environment. Thanks Annie