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Posted to users@cloudstack.apache.org by Nando Beifiori <na...@gmail.com> on 2017/02/10 15:28:02 UTC
Intel v3 and v4 CPUs in the same cluster
Hi all,
quick but very important question: I have a cluster with Intel Xeon E5-2667
v3 CPUs and I need to add another host, but my provider has replaced the v3
with the v4 of the same CPU.
The differences are:
- Lithography (22nm > 14nm)
- Cache size (20MB > 25MB)
- Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
- Intel TSX-NI feature which is present in v4 but not in the v3.
Frequency, turbo frequency and cores are exactly the same.
Would it be possible to add the new host to the same cluster or should I
create a new cluster or maybe look for a provider that still has the v3 CPU?
Cloudstack version is 4.9 and hosts use Centos 7.2.
Thanks in advance
Re: Intel v3 and v4 CPUs in the same cluster
Posted by Nando Beifiori <na...@gmail.com>.
Thanks for the clarification.
In this specific case v3 is a Haswell-noTSX while v4 is a Broadwell, with
the latter that has 6 more features (according to the cpu_map.xml )
So, I reckon an agent.properties set as follows would work:
guest.cpu.mode=custom
guest.cpu.model=Haswell-noTSX
Thanks again
On 10 February 2017 at 19:07, ilya <il...@gmail.com> wrote:
> https://media.readthedocs.org/pdf/cloudstack-installation/4.
> 8/cloudstack-installation.pdf
>
> Page 76 explains it.. you want for CPU instructions sets to match and be
> consistent if you plan to run v3 and v4 cpus in the same cluster.
>
> Regards
> ilya
>
> On 2/10/17 8:23 AM, Rafael Weingärtner wrote:
> > From my experience, yes it would work.
> >
> > At the end what matter are the CPU capabilities, meaning the instructions
> > tha can be used by operating systems (O.S) and their processes, in this
> > case, VMs can be considered processes in the hypervisor (hypervisors are
> > OS). We normally do the masking to hide features that may only be
> available
> > in one host or other; when you migrate a VM of a host (without masking),
> if
> > the VM ends up in a host that does not have the same CPU features it may
> > crash or present unexpected behaviors.
> >
> > On Fri, Feb 10, 2017 at 11:15 AM, Nando Beifiori <
> nandobeifiori@gmail.com>
> > wrote:
> >
> >> Hi Rafael,
> >>
> >> in this case the hypervisor is KVM and I think it supports masking, but
> let
> >> me check if I got it right:
> >>
> >> if the CPU is not exactly the same the features can be masked using
> >> hypervisor's capabilities.
> >>
> >> Does it mean that if the CPU has the exact same features but different
> >> frequency for example it would work?
> >>
> >> Thanks
> >>
> >> On 10 February 2017 at 15:46, Rafael Weingärtner <
> >> rafaelweingartner@gmail.com> wrote:
> >>
> >>> It depends on your hypervisor.
> >>> For XenServer, you should check the CPU feature you have and if the CPU
> >>> supports masking [1].
> >>>
> >>> xe host-cpu-info
> >>>>
> >>>
> >>> Look for the "features" information, and then check if your hardware
> guy
> >>> can provide a processor with similar features or one that supports
> >> masking
> >>> the same features as your current servers' CPUs.
> >>>
> >>> [1] https://support.citrix.com/article/CTX127059
> >>>
> >>> On Fri, Feb 10, 2017 at 10:28 AM, Nando Beifiori <
> >> nandobeifiori@gmail.com>
> >>> wrote:
> >>>
> >>>> Hi all,
> >>>>
> >>>> quick but very important question: I have a cluster with Intel Xeon
> >>> E5-2667
> >>>> v3 CPUs and I need to add another host, but my provider has replaced
> >> the
> >>> v3
> >>>> with the v4 of the same CPU.
> >>>>
> >>>> The differences are:
> >>>>
> >>>> - Lithography (22nm > 14nm)
> >>>> - Cache size (20MB > 25MB)
> >>>> - Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
> >>>> - Intel TSX-NI feature which is present in v4 but not in the v3.
> >>>>
> >>>> Frequency, turbo frequency and cores are exactly the same.
> >>>> Would it be possible to add the new host to the same cluster or should
> >> I
> >>>> create a new cluster or maybe look for a provider that still has the
> v3
> >>>> CPU?
> >>>>
> >>>> Cloudstack version is 4.9 and hosts use Centos 7.2.
> >>>>
> >>>> Thanks in advance
> >>>>
> >>>
> >>>
> >>>
> >>> --
> >>> Rafael Weingärtner
> >>>
> >>
> >
> >
> >
>
Re: Intel v3 and v4 CPUs in the same cluster
Posted by ilya <il...@gmail.com>.
https://media.readthedocs.org/pdf/cloudstack-installation/4.8/cloudstack-installation.pdf
Page 76 explains it.. you want for CPU instructions sets to match and be
consistent if you plan to run v3 and v4 cpus in the same cluster.
Regards
ilya
On 2/10/17 8:23 AM, Rafael Weing�rtner wrote:
> From my experience, yes it would work.
>
> At the end what matter are the CPU capabilities, meaning the instructions
> tha can be used by operating systems (O.S) and their processes, in this
> case, VMs can be considered processes in the hypervisor (hypervisors are
> OS). We normally do the masking to hide features that may only be available
> in one host or other; when you migrate a VM of a host (without masking), if
> the VM ends up in a host that does not have the same CPU features it may
> crash or present unexpected behaviors.
>
> On Fri, Feb 10, 2017 at 11:15 AM, Nando Beifiori <na...@gmail.com>
> wrote:
>
>> Hi Rafael,
>>
>> in this case the hypervisor is KVM and I think it supports masking, but let
>> me check if I got it right:
>>
>> if the CPU is not exactly the same the features can be masked using
>> hypervisor's capabilities.
>>
>> Does it mean that if the CPU has the exact same features but different
>> frequency for example it would work?
>>
>> Thanks
>>
>> On 10 February 2017 at 15:46, Rafael Weing�rtner <
>> rafaelweingartner@gmail.com> wrote:
>>
>>> It depends on your hypervisor.
>>> For XenServer, you should check the CPU feature you have and if the CPU
>>> supports masking [1].
>>>
>>> xe host-cpu-info
>>>>
>>>
>>> Look for the "features" information, and then check if your hardware guy
>>> can provide a processor with similar features or one that supports
>> masking
>>> the same features as your current servers' CPUs.
>>>
>>> [1] https://support.citrix.com/article/CTX127059
>>>
>>> On Fri, Feb 10, 2017 at 10:28 AM, Nando Beifiori <
>> nandobeifiori@gmail.com>
>>> wrote:
>>>
>>>> Hi all,
>>>>
>>>> quick but very important question: I have a cluster with Intel Xeon
>>> E5-2667
>>>> v3 CPUs and I need to add another host, but my provider has replaced
>> the
>>> v3
>>>> with the v4 of the same CPU.
>>>>
>>>> The differences are:
>>>>
>>>> - Lithography (22nm > 14nm)
>>>> - Cache size (20MB > 25MB)
>>>> - Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
>>>> - Intel TSX-NI feature which is present in v4 but not in the v3.
>>>>
>>>> Frequency, turbo frequency and cores are exactly the same.
>>>> Would it be possible to add the new host to the same cluster or should
>> I
>>>> create a new cluster or maybe look for a provider that still has the v3
>>>> CPU?
>>>>
>>>> Cloudstack version is 4.9 and hosts use Centos 7.2.
>>>>
>>>> Thanks in advance
>>>>
>>>
>>>
>>>
>>> --
>>> Rafael Weing�rtner
>>>
>>
>
>
>
Re: Intel v3 and v4 CPUs in the same cluster
Posted by Rafael Weingärtner <ra...@gmail.com>.
From my experience, yes it would work.
At the end what matter are the CPU capabilities, meaning the instructions
tha can be used by operating systems (O.S) and their processes, in this
case, VMs can be considered processes in the hypervisor (hypervisors are
OS). We normally do the masking to hide features that may only be available
in one host or other; when you migrate a VM of a host (without masking), if
the VM ends up in a host that does not have the same CPU features it may
crash or present unexpected behaviors.
On Fri, Feb 10, 2017 at 11:15 AM, Nando Beifiori <na...@gmail.com>
wrote:
> Hi Rafael,
>
> in this case the hypervisor is KVM and I think it supports masking, but let
> me check if I got it right:
>
> if the CPU is not exactly the same the features can be masked using
> hypervisor's capabilities.
>
> Does it mean that if the CPU has the exact same features but different
> frequency for example it would work?
>
> Thanks
>
> On 10 February 2017 at 15:46, Rafael Weingärtner <
> rafaelweingartner@gmail.com> wrote:
>
> > It depends on your hypervisor.
> > For XenServer, you should check the CPU feature you have and if the CPU
> > supports masking [1].
> >
> > xe host-cpu-info
> > >
> >
> > Look for the "features" information, and then check if your hardware guy
> > can provide a processor with similar features or one that supports
> masking
> > the same features as your current servers' CPUs.
> >
> > [1] https://support.citrix.com/article/CTX127059
> >
> > On Fri, Feb 10, 2017 at 10:28 AM, Nando Beifiori <
> nandobeifiori@gmail.com>
> > wrote:
> >
> > > Hi all,
> > >
> > > quick but very important question: I have a cluster with Intel Xeon
> > E5-2667
> > > v3 CPUs and I need to add another host, but my provider has replaced
> the
> > v3
> > > with the v4 of the same CPU.
> > >
> > > The differences are:
> > >
> > > - Lithography (22nm > 14nm)
> > > - Cache size (20MB > 25MB)
> > > - Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
> > > - Intel TSX-NI feature which is present in v4 but not in the v3.
> > >
> > > Frequency, turbo frequency and cores are exactly the same.
> > > Would it be possible to add the new host to the same cluster or should
> I
> > > create a new cluster or maybe look for a provider that still has the v3
> > > CPU?
> > >
> > > Cloudstack version is 4.9 and hosts use Centos 7.2.
> > >
> > > Thanks in advance
> > >
> >
> >
> >
> > --
> > Rafael Weingärtner
> >
>
--
Rafael Weingärtner
Re: Intel v3 and v4 CPUs in the same cluster
Posted by Nando Beifiori <na...@gmail.com>.
Hi Rafael,
in this case the hypervisor is KVM and I think it supports masking, but let
me check if I got it right:
if the CPU is not exactly the same the features can be masked using
hypervisor's capabilities.
Does it mean that if the CPU has the exact same features but different
frequency for example it would work?
Thanks
On 10 February 2017 at 15:46, Rafael Weingärtner <
rafaelweingartner@gmail.com> wrote:
> It depends on your hypervisor.
> For XenServer, you should check the CPU feature you have and if the CPU
> supports masking [1].
>
> xe host-cpu-info
> >
>
> Look for the "features" information, and then check if your hardware guy
> can provide a processor with similar features or one that supports masking
> the same features as your current servers' CPUs.
>
> [1] https://support.citrix.com/article/CTX127059
>
> On Fri, Feb 10, 2017 at 10:28 AM, Nando Beifiori <na...@gmail.com>
> wrote:
>
> > Hi all,
> >
> > quick but very important question: I have a cluster with Intel Xeon
> E5-2667
> > v3 CPUs and I need to add another host, but my provider has replaced the
> v3
> > with the v4 of the same CPU.
> >
> > The differences are:
> >
> > - Lithography (22nm > 14nm)
> > - Cache size (20MB > 25MB)
> > - Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
> > - Intel TSX-NI feature which is present in v4 but not in the v3.
> >
> > Frequency, turbo frequency and cores are exactly the same.
> > Would it be possible to add the new host to the same cluster or should I
> > create a new cluster or maybe look for a provider that still has the v3
> > CPU?
> >
> > Cloudstack version is 4.9 and hosts use Centos 7.2.
> >
> > Thanks in advance
> >
>
>
>
> --
> Rafael Weingärtner
>
Re: Intel v3 and v4 CPUs in the same cluster
Posted by Rafael Weingärtner <ra...@gmail.com>.
It depends on your hypervisor.
For XenServer, you should check the CPU feature you have and if the CPU
supports masking [1].
xe host-cpu-info
>
Look for the "features" information, and then check if your hardware guy
can provide a processor with similar features or one that supports masking
the same features as your current servers' CPUs.
[1] https://support.citrix.com/article/CTX127059
On Fri, Feb 10, 2017 at 10:28 AM, Nando Beifiori <na...@gmail.com>
wrote:
> Hi all,
>
> quick but very important question: I have a cluster with Intel Xeon E5-2667
> v3 CPUs and I need to add another host, but my provider has replaced the v3
> with the v4 of the same CPU.
>
> The differences are:
>
> - Lithography (22nm > 14nm)
> - Cache size (20MB > 25MB)
> - Max Memory Bandwidth (68 GB/s > 76.8 GB/s)
> - Intel TSX-NI feature which is present in v4 but not in the v3.
>
> Frequency, turbo frequency and cores are exactly the same.
> Would it be possible to add the new host to the same cluster or should I
> create a new cluster or maybe look for a provider that still has the v3
> CPU?
>
> Cloudstack version is 4.9 and hosts use Centos 7.2.
>
> Thanks in advance
>
--
Rafael Weingärtner