From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Snitzer Subject: Re: How to properly benchmark dm-cache Date: Fri, 1 Sep 2017 11:58:30 -0400 Message-ID: <20170901155829.GA17442@redhat.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Remington Brasga Cc: "dm-devel@redhat.com" , ejt@redhat.com List-Id: dm-devel.ids On Thu, Aug 31 2017 at 5:29pm -0400, Remington Brasga wrote: > Hi, I'm trying to benchmark dm-cache, but I'm having trouble getting the > benchmark to show positive results. I've tried TPC-B, TPC-C, TPC-H, SQL, > and a handful of other, but I think because they are simulations they > don't generate the `hot spots' required to promote blocks to the cache. > > I know it's easy to show results using FIO with a specific configuration, > but I was hoping to use a real benchmark like the ones I've tried. > > Does anyone have a good set of benchmarks that shows positive results? Hi Remi, Which kernel are you testing? I know Sanjay Rao (cc'd) has done various dm-cache testing with an OLTP workload against an Oracle DB and that he has seen very solid results with the latest dm-cache. I'm not sure if he, or others, tried any of the TPC variants but hopefully Sanjay can respond with where/how he got dm-cache to respond well to his tests. Mike