Marcelo Tosatti wrote: > On Fri, May 08, 2009 at 10:45:52AM -0400, Gregory Haskins wrote: >> Marcelo Tosatti wrote: >>> On Fri, May 08, 2009 at 10:55:37AM +0300, Avi Kivity wrote: >>> >>>> Marcelo Tosatti wrote: >>>> >>>>> Also it would be interesting to see the MMIO comparison with EPT/NPT, >>>>> it probably sucks much less than what you're seeing. >>>>> >>>>> >>>> Why would NPT improve mmio? If anything, it would be worse, since the >>>> processor has to do the nested walk. >>>> >>>> Of course, these are newer machines, so the absolute results as well as >>>> the difference will be smaller. >>>> >>> Quad-Core AMD Opteron(tm) Processor 2358 SE 2.4GHz: >>> >>> NPT enabled: >>> test 0: 3088633284634 - 3059375712321 = 29257572313 >>> test 1: 3121754636397 - 3088633419760 = 33121216637 >>> test 2: 3204666462763 - 3121754668573 = 82911794190 >>> >>> NPT disabled: >>> test 0: 3638061646250 - 3609416811687 = 28644834563 >>> test 1: 3669413430258 - 3638061771291 = 31351658967 >>> test 2: 3736287253287 - 3669413463506 = 66873789781 >>> >>> >> Thanks for running that. Its interesting to see that NPT was in fact >> worse as Avi predicted. >> >> Would you mind if I graphed the result and added this data to my wiki? >> If so, could you adjust the tsc result into IOPs using the proper >> time-base and the test_count you ran with? I can show a graph with the >> data as is and the relative differences will properly surface..but it >> would be nice to have apples to apples in terms of IOPS units with my >> other run. >> >> -Greg > > Please, that'll be nice. > > Quad-Core AMD Opteron(tm) Processor 2358 SE > > host: 2.6.30-rc2 > guest: 2.6.29.1-102.fc11.x86_64 > > test_count=1000000, tsc freq=2402882804 Hz > > NPT disabled: > > test 0 = 2771200766 > test 1 = 3018726738 > test 2 = 6414705418 > test 3 = 2890332864 > > NPT enabled: > > test 0 = 2908604045 > test 1 = 3174687394 > test 2 = 7912464804 > test 3 = 3046085805 > DL380 G6, 1-E5540, 6 GB RAM, SMT enabled: host: 2.6.30-rc3 guest: fedora 9, 2.6.27.21-78.2.41.fc9.x86_64 with EPT test 0: 543617607291 - 518146439877 = 25471167414 test 1: 572568176856 - 543617703004 = 28950473852 test 2: 630182158139 - 572568269792 = 57613888347 without EPT test 0: 1383532195307 - 1358052032086 = 25480163221 test 1: 1411587055210 - 1383532318617 = 28054736593 test 2: 1471446356172 - 1411587194600 = 59859161572 david > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
