From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: Re: [PATCH RFC V4 0/5] kvm : Paravirt-spinlock support for KVM guests Date: Mon, 16 Jan 2012 19:13:07 +0530 Message-ID: <4F14296B.4070003@linux.vnet.ibm.com> References: <20120114182501.8604.68416.sendpatchset@oc5400248562.ibm.com> <3EC1B881-0724-49E3-B892-F40BEB07D15D@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Cc: Jeremy Fitzhardinge , Greg Kroah-Hartman , linux-doc@vger.kernel.org, Peter Zijlstra , Jan Kiszka , Virtualization , Paul Mackerras , "H. Peter Anvin" , Stefano Stabellini , Xen , Dave Jiang , KVM , Glauber Costa , X86 , Ingo Molnar , Avi Kivity , Rik van Riel , Konrad Rzeszutek Wilk , Srivatsa Vaddagiri , Sasha Levin , Sedat Dilek , Thomas Gleixner , LKML , Dave Hansen Return-path: In-Reply-To: <3EC1B881-0724-49E3-B892-F40BEB07D15D@suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org List-Id: kvm.vger.kernel.org On 01/16/2012 09:27 AM, Alexander Graf wrote: > [...] >> Result for PLE machine: >> ====================== >> Machine : IBM xSeries with Intel(R) Xeon(R) X7560 2.27GHz CPU with 32/64 core, with 8 >> online cores and 4*64GB RAM >> >> Kernbench: >> BASE BASE+patch %improvement >> mean (sd) mean (sd) >> Scenario A: >> case 1x: 161.263 (56.518) 159.635 (40.5621) 1.00953 >> case 2x: 190.748 (61.2745) 190.606 (54.4766) 0.0744438 >> case 3x: 227.378 (100.215) 225.442 (92.0809) 0.851446 >> >> Scenario B: >> 446.104 (58.54 ) 433.12733 (54.476) 2.91 >> >> Dbench: >> Throughput is in MB/sec >> NRCLIENTS BASE BASE+patch %improvement >> mean (sd) mean (sd) >> 8 1.101190 (0.875082) 1.700395 (0.846809) 54.4143 >> 16 1.524312 (0.120354) 1.477553 (0.058166) -3.06755 >> 32 2.143028 (0.157103) 2.090307 (0.136778) -2.46012 > > So on a very contended system we're actually slower? Is this expected? > > I think, the result is interesting because its PLE machine. I have to experiment more with parameters, SPIN_THRESHOLD, and also may be ple_gap and ple_window. > Alex > > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Raghavendra K T Subject: Re: [PATCH RFC V4 0/5] kvm : Paravirt-spinlock support for KVM guests Date: Mon, 16 Jan 2012 19:13:07 +0530 Message-ID: <4F14296B.4070003@linux.vnet.ibm.com> References: <20120114182501.8604.68416.sendpatchset@oc5400248562.ibm.com> <3EC1B881-0724-49E3-B892-F40BEB07D15D@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <3EC1B881-0724-49E3-B892-F40BEB07D15D@suse.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Alexander Graf Cc: Jeremy Fitzhardinge , Greg Kroah-Hartman , linux-doc@vger.kernel.org, Peter Zijlstra , Jan Kiszka , Virtualization , Paul Mackerras , "H. Peter Anvin" , Stefano Stabellini , Xen , Dave Jiang , KVM , Glauber Costa , X86 , Ingo Molnar , Avi Kivity , Rik van Riel , Konrad Rzeszutek Wilk , Srivatsa Vaddagiri , Sasha Levin , Sedat Dilek , Thomas Gleixner , LKML , Dave Hansen List-Id: virtualization@lists.linuxfoundation.org On 01/16/2012 09:27 AM, Alexander Graf wrote: > [...] >> Result for PLE machine: >> ====================== >> Machine : IBM xSeries with Intel(R) Xeon(R) X7560 2.27GHz CPU with 32/64 core, with 8 >> online cores and 4*64GB RAM >> >> Kernbench: >> BASE BASE+patch %improvement >> mean (sd) mean (sd) >> Scenario A: >> case 1x: 161.263 (56.518) 159.635 (40.5621) 1.00953 >> case 2x: 190.748 (61.2745) 190.606 (54.4766) 0.0744438 >> case 3x: 227.378 (100.215) 225.442 (92.0809) 0.851446 >> >> Scenario B: >> 446.104 (58.54 ) 433.12733 (54.476) 2.91 >> >> Dbench: >> Throughput is in MB/sec >> NRCLIENTS BASE BASE+patch %improvement >> mean (sd) mean (sd) >> 8 1.101190 (0.875082) 1.700395 (0.846809) 54.4143 >> 16 1.524312 (0.120354) 1.477553 (0.058166) -3.06755 >> 32 2.143028 (0.157103) 2.090307 (0.136778) -2.46012 > > So on a very contended system we're actually slower? Is this expected? > > I think, the result is interesting because its PLE machine. I have to experiment more with parameters, SPIN_THRESHOLD, and also may be ple_gap and ple_window. > Alex > >