One off question: Hot vertical scaling of a KVM?

One off question: Hot vertical scaling of a KVM?

[ROZUMNY, VICTOR]

Hello-

Your site states that one off questions might could be answered via email so here I am. 

I have limited knowledge of KVM, but it is my understanding that in order to vertically  scale RAM for a KVM the guest needs to be shut down, resized, and rebooted, resulting in a 5-10 minute interruption of service.

Is this true and if so do you know of any efforts to change this behavior?

Thank you!

v.

Vic Rozumny | Principal Technical Architect
AIC - AT&T Integrated Cloud | Complex Engineering

Re: One off question: Hot vertical scaling of a KVM?

[Bandan Das]

"ROZUMNY, VICTOR" <vr9723@att.com> writes:

> Hello-
>
> Your site states that one off questions might could be answered via
> email so here I am.
>
> I have limited knowledge of KVM, but it is my understanding that in
> order to vertically scale RAM for a KVM the guest needs to be shut
> down, resized, and rebooted, resulting in a 5-10 minute interruption
> of service.
What's vertical scaling ? You mean, increase the amount of memory
the guest sees ? You could use Qemu memory hotplug I think but that
requires that the guest has been booted with enough number of
"dimm" slots.

Bandan

> Is this true and if so do you know of any efforts to change this
> behavior?
>
> Thank you!
>
> v.
>
> Vic Rozumny | Principal Technical Architect AIC - AT&T Integrated
> Cloud | Complex Engineering
>
>
>
>
>
> --
> 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

RE: One off question: Hot vertical scaling of a KVM?

[ROZUMNY, VICTOR]

Bandan-

Thank you for the quick response and for your time.

 To answer your question, yes, we have a need to dynamically increase the available RAM that a KVM guest has available to it. i.e. change from 16GB to 32GB with minimal or no interruption of service. 

I have taken a look at Qemu and from what I can tell however it seems to only allow for the dynamic increase of processors(s) and their speed(s), or am I missing something here?

Do you know of any similar program that would allow for the scaling of RAM for one node\guest?

We are looking to implement this solution in an OpenStack cloud. 

Thanks again.

v.



-----Original Message-----
From: Bandan Das [mailto:bsd@redhat.com] 
Sent: Wednesday, August 19, 2015 5:48 PM
To: ROZUMNY, VICTOR
Cc: kvm@vger.kernel.org; WEINSTEIN, MICHAEL A
Subject: Re: One off question: Hot vertical scaling of a KVM?

"ROZUMNY, VICTOR" <vr9723@att.com> writes:

> Hello-
>
> Your site states that one off questions might could be answered via
> email so here I am.
>
> I have limited knowledge of KVM, but it is my understanding that in
> order to vertically scale RAM for a KVM the guest needs to be shut
> down, resized, and rebooted, resulting in a 5-10 minute interruption
> of service.
What's vertical scaling ? You mean, increase the amount of memory
the guest sees ? You could use Qemu memory hotplug I think but that
requires that the guest has been booted with enough number of
"dimm" slots.

Bandan

> Is this true and if so do you know of any efforts to change this
> behavior?
>
> Thank you!
>
> v.
>
> Vic Rozumny | Principal Technical Architect AIC - AT&T Integrated
> Cloud | Complex Engineering
>
>
>
>
>
> --
> 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