From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tiwei Bie Subject: Re: [PATCH] vhost: adaptively batch small guest memory copies Date: Fri, 8 Sep 2017 18:38:29 +0800 Message-ID: <20170908103829.GA23326@debian-ZGViaWFuCg> References: <20170824021939.21306-1-tiwei.bie@intel.com> <20170908074108.GE9736@yliu-home> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Cc: dev@dpdk.org, maxime.coquelin@redhat.com, Zhihong Wang , Zhiyong Yang To: Yuanhan Liu Return-path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 73DF07CBC for ; Fri, 8 Sep 2017 12:38:07 +0200 (CEST) Content-Disposition: inline In-Reply-To: <20170908074108.GE9736@yliu-home> List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On Fri, Sep 08, 2017 at 03:41:08PM +0800, Yuanhan Liu wrote: > On Thu, Aug 24, 2017 at 10:19:39AM +0800, Tiwei Bie wrote: > > This patch adaptively batches the small guest memory copies. > > By batching the small copies, the efficiency of executing the > > memory LOAD instructions can be improved greatly, because the > > memory LOAD latency can be effectively hidden by the pipeline. > > We saw great performance boosts for small packets PVP test. > > > > This patch improves the performance for small packets, and has > > distinguished the packets by size. So although the performance > > for big packets doesn't change, it makes it relatively easy to > > do some special optimizations for the big packets too. > > The number showed in other replies looks really impressive. Great work! > This patch also looks good to me. I have one minor comment though. > > [...] > > +/* > > + * Structure contains the info for each batched memory copy. > > + */ > > +struct burst_copy_elem { > > + void *dst; > > + void *src; > > + uint32_t len; > > + uint64_t log_addr; > > +}; > > Like the title says, it's more about batch (but not burst). Also, it's > not a good idea to mix burst and batch. I'd suggest you to use the term > "batch" consistently. > Okay, I'll change it. Thank you! :-) Best regards, Tiwei Bie