On 08/16/10 17:09, Alex Rixhardson wrote: > Thank you a lot for the tip - you were right. The 5.5 guest is using > virtio, but 4.5 is not. So, this is the reason. > > Adding <model type='virtio' /> to the config file unfortunately > doesn't help - the network card is not recognized by the guest. Do I > need to install something extra on the guest RHEL 4.5? RHEL4.8 is the first RHEL4 version to support virtio devices. David > > Regards, > Alex > > On Tue, Aug 17, 2010 at 12:05 AM, Alex Rixhardson > <alexrixhardson@xxxxxxxxx> wrote: >> virtio...I think :-). >> >> How could I confirm that? >> >> Regards, >> Alex >> >> On Mon, Aug 16, 2010 at 11:56 PM, Dor Laor <dlaor@xxxxxxxxxx> wrote: >>> On 08/17/2010 12:51 AM, Alex Rixhardson wrote: >>>> >>>> I tried with 'notsc divider=10' (since it's 64 bit guest), but the >>>> results are the still same :-(. The guest is idle at the time of >>>> testing. It has 2 CPU and 1024 MB RAM available. >>> >>> Hmm, are you using e1000 or virtio for the 4.5 guest? >>> e1000 should be slow since it's less suitable for virtualization (3 >>> mmio/packet) >>> >>> >>>> >>>> On Mon, Aug 16, 2010 at 11:35 PM, Dor Laor<dlaor@xxxxxxxxxx> wrote: >>>>> >>>>> On 08/17/2010 12:22 AM, Alex Rixhardson wrote: >>>>>> >>>>>> Thanks for the suggestion. >>>>>> >>>>>> I tried with the netperf. I ran netserver on host and netperf on RHEL >>>>>> 5.5 and RHEL 4.5 guests. This are the results of 60 seconds long >>>>>> tests: >>>>>> >>>>>> RHEL 4.5 guest: >>>>>> Throughput (10^6bits/sec) = 145.80 >>>>> >>>>> At least it bought you another 5Mb/s over iperf ... >>>>> >>>>> It might be time related, 5.5 has kvmclock but rhel4 does not. >>>>> If it's 64 bit guest add this to the 4.5 guest cmdline 'notsc >>>>> divider=10'. >>>>> If it's 32 use 'clock=pmtmr divider=10'. >>>>> The divider is probably new and is in rhel4.8 only, it's ok w/o it too. >>>>> >>>>> What's the host load for the 4.5 guest? >>>>> >>>>>> >>>>>> RHEL 5.5 guest: >>>>>> Throughput (10^6bits/sec) = 3760.24 >>>>>> >>>>>> The results are really bad on RHEL 4.5 guest. What could be wrong? >>>>>> >>>>>> Regards, >>>>>> Alex >>>>>> >>>>>> On Mon, Aug 16, 2010 at 9:49 PM, Dor Laor<dlaor@xxxxxxxxxx> wrote: >>>>>>> >>>>>>> On 08/16/2010 10:00 PM, Alex Rixhardson wrote: >>>>>>>> >>>>>>>> Hi guys, >>>>>>>> >>>>>>>> I have the following configuration: >>>>>>>> >>>>>>>> 1. host is RHEL 5.5, 64bit with KVM (version that comes out of the box >>>>>>>> with RHEL 5.5) >>>>>>>> 2. two guests: >>>>>>>> 2a: RHEL 5.5, 32bit, >>>>>>>> 2b: RHEL 4.5, 64bit >>>>>>>> >>>>>>>> If I run iperf between host RHEL 5.5 and guest RHEL 5.5 inside the >>>>>>>> virtual network subnet I get great results (> 4Gbit/sec). But if >>>>>>>> I >>>>>>>> run >>>>>>>> iperf between guest RHEL 4.5 and either of the two RHELs 5.5 I get bad >>>>>>>> network performance (around 140Mbit/sec). >>>>>>> >>>>>>> Please try netperf, iperf known to be buggy and might consume cpu w/o >>>>>>> real >>>>>>> justification >>>>>>> >>>>>>>> >>>>>>>> The configuration was made thru virtual-manager utility, nothing >>>>>>>> special. I just added virtual network device to both guests. >>>>>>>> >>>>>>>> Could you guys give me some tips on what should I check? >>>>>>>> >>>>>>>> Regards, >>>>>>>> Alex >>>>>>>> -- >>>>>>>> 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 >>>>> >>>>> >>>> -- >>>> 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 > -- 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
