* RHEL 4.5 guest virtual network performace @ 2010-08-16 19:00 Alex Rixhardson 2010-08-16 19:49 ` Dor Laor 0 siblings, 1 reply; 9+ messages in thread From: Alex Rixhardson @ 2010-08-16 19:00 UTC (permalink / raw) To: kvm 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). 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 ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 19:00 RHEL 4.5 guest virtual network performace Alex Rixhardson @ 2010-08-16 19:49 ` Dor Laor 2010-08-16 21:22 ` Alex Rixhardson 0 siblings, 1 reply; 9+ messages in thread From: Dor Laor @ 2010-08-16 19:49 UTC (permalink / raw) To: Alex Rixhardson; +Cc: kvm 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 19:49 ` Dor Laor @ 2010-08-16 21:22 ` Alex Rixhardson 2010-08-16 21:35 ` Dor Laor 0 siblings, 1 reply; 9+ messages in thread From: Alex Rixhardson @ 2010-08-16 21:22 UTC (permalink / raw) To: dlaor, kvm 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 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@redhat.com> 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@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 21:22 ` Alex Rixhardson @ 2010-08-16 21:35 ` Dor Laor 2010-08-16 21:51 ` Alex Rixhardson 0 siblings, 1 reply; 9+ messages in thread From: Dor Laor @ 2010-08-16 21:35 UTC (permalink / raw) To: Alex Rixhardson; +Cc: kvm 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@redhat.com> 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@vger.kernel.org >>> 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 21:35 ` Dor Laor @ 2010-08-16 21:51 ` Alex Rixhardson 2010-08-16 21:56 ` Dor Laor 0 siblings, 1 reply; 9+ messages in thread From: Alex Rixhardson @ 2010-08-16 21:51 UTC (permalink / raw) To: dlaor, kvm 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. On Mon, Aug 16, 2010 at 11:35 PM, Dor Laor <dlaor@redhat.com> 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@redhat.com> 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@vger.kernel.org >>>> 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@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 21:51 ` Alex Rixhardson @ 2010-08-16 21:56 ` Dor Laor 2010-08-16 22:05 ` Alex Rixhardson 0 siblings, 1 reply; 9+ messages in thread From: Dor Laor @ 2010-08-16 21:56 UTC (permalink / raw) To: Alex Rixhardson; +Cc: kvm 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@redhat.com> 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@redhat.com> 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@vger.kernel.org >>>>> 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@vger.kernel.org >>> 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 21:56 ` Dor Laor @ 2010-08-16 22:05 ` Alex Rixhardson 2010-08-16 23:09 ` Alex Rixhardson 0 siblings, 1 reply; 9+ messages in thread From: Alex Rixhardson @ 2010-08-16 22:05 UTC (permalink / raw) To: dlaor, kvm virtio...I think :-). How could I confirm that? Regards, Alex On Mon, Aug 16, 2010 at 11:56 PM, Dor Laor <dlaor@redhat.com> 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@redhat.com> 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@redhat.com> 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@vger.kernel.org >>>>>> 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@vger.kernel.org >>>> 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@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 22:05 ` Alex Rixhardson @ 2010-08-16 23:09 ` Alex Rixhardson 2010-08-17 1:22 ` David S. Ahern 0 siblings, 1 reply; 9+ messages in thread From: Alex Rixhardson @ 2010-08-16 23:09 UTC (permalink / raw) To: dlaor, kvm 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? Regards, Alex On Tue, Aug 17, 2010 at 12:05 AM, Alex Rixhardson <alexrixhardson@gmail.com> wrote: > virtio...I think :-). > > How could I confirm that? > > Regards, > Alex > > On Mon, Aug 16, 2010 at 11:56 PM, Dor Laor <dlaor@redhat.com> 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@redhat.com> 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@redhat.com> 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@vger.kernel.org >>>>>>> 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@vger.kernel.org >>>>> 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@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> > ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: RHEL 4.5 guest virtual network performace 2010-08-16 23:09 ` Alex Rixhardson @ 2010-08-17 1:22 ` David S. Ahern 0 siblings, 0 replies; 9+ messages in thread From: David S. Ahern @ 2010-08-17 1:22 UTC (permalink / raw) To: Alex Rixhardson; +Cc: dlaor, kvm 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@gmail.com> wrote: >> virtio...I think :-). >> >> How could I confirm that? >> >> Regards, >> Alex >> >> On Mon, Aug 16, 2010 at 11:56 PM, Dor Laor <dlaor@redhat.com> 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@redhat.com> 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@redhat.com> 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@vger.kernel.org >>>>>>>> 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@vger.kernel.org >>>>>> 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@vger.kernel.org >>>> 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@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2010-08-17 1:22 UTC | newest] Thread overview: 9+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2010-08-16 19:00 RHEL 4.5 guest virtual network performace Alex Rixhardson 2010-08-16 19:49 ` Dor Laor 2010-08-16 21:22 ` Alex Rixhardson 2010-08-16 21:35 ` Dor Laor 2010-08-16 21:51 ` Alex Rixhardson 2010-08-16 21:56 ` Dor Laor 2010-08-16 22:05 ` Alex Rixhardson 2010-08-16 23:09 ` Alex Rixhardson 2010-08-17 1:22 ` David S. Ahern
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