git.net

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: KVM Max Guests Limit


afaik not - but I did run once or twice intom perhaps looselym connected
issue - ACS reports 100% of host RAM (makes sense) asavailable for VM
deployment to ACS - so in 1-2 cases I did run into out of memory killer,
crashing my VMs.

It would be great to have some amount of "reserve RAM" for host OS - or
simply have PER HOST RAM disableTreshold setting, similar to cluster level
"cluster.memory.allocated.capacity.disablethreshold", just on host level...

On Fri, 9 Nov 2018 at 12:03, Rafael Weingärtner <rafaelweingartner@xxxxxxxxx>
wrote:

> Do we need these logical constraints in ACS at all?
>
> On Fri, Nov 9, 2018 at 6:57 AM Wido den Hollander <wido@xxxxxxxxx> wrote:
>
> >
> >
> > On 11/8/18 11:20 PM, Simon Weller wrote:
> > > I think these is legacy and a guess back in the day. It was 50 at one
> > point and it was lifted higher a few releases. ago.
> > >
> >
> > I see. I'm about to do a test with a bunch of 128GB hypervisors and
> > spawning a lot of 128M VMs. Trying to see where the limit might be and
> > also stress the VR a bit by loading a lot of DHCP entries.
> >
> > Wido
> >
> > >
> > >
> > >
> > > ________________________________
> > > From: Ivan Kudryavtsev <kudryavtsev_ia@xxxxxxxxx>
> > > Sent: Thursday, November 8, 2018 3:58 PM
> > > To: dev
> > > Subject: Re: KVM Max Guests Limit
> > >
> > > Hi all, +1 for higher numbers.
> > >
> > > чт, 8 нояб. 2018 г. в 16:32, Wido den Hollander <wido@xxxxxxxxx>:
> > >
> > >> Hi,
> > >>
> > >> I see that for KVM we set the limit to 144 guests by default, can
> > >> anybody tell me why we have this limit set to 144?
> > >>
> > >> Searching a bit I found this:
> > >> https://access.redhat.com/articles/rhel-kvm-limits
> > >>
> > >> "This guest limit does not apply to Red Hat Enterprise Linux with
> > >> Unlimited Guests. There is no guest limit for Red Hat Enterprise
> > >> Virtualization"
> > >>
> > >> There is always a limit somewhere, but why do we set it to 144?
> > >>
> > >> I would personally vote for increasing this to 500 or something so
> that
> > >> users don't run into it that easily.
> > >>
> > >> Also, the log line is printed in DEBUG mode only when a host reaches
> > >> this limit, so I created a PR to set this to INFO:
> > >> https://github.com/apache/cloudstack/pull/3013
> > >>
> > >> Any input?
> > >>
> > >> Wido
> > >>
> > >
> > >
> > > --
> > > With best regards, Ivan Kudryavtsev
> > > Bitworks LLC
> > > Cell RU: +7-923-414-1515
> > > Cell USA: +1-201-257-1512
> > > WWW: http://bitworks.software/ <http://bw-sw.com/>
> > >
> >
>
>
> --
> Rafael Weingärtner
>


-- 

Andrija Panić