[Ci-users] AltArch support in CI (status update)

Wed Jul 26 14:38:53 UTC 2017
Brian Stinson <brian at bstinson.com>

On Jul 26 15:04, Fabian Arrotin wrote:
> On 25/07/17 17:45, Brian Stinson wrote:
> > On Jul 14 16:25, Fabian Arrotin wrote:
> <snip>
> > 
> > 
> > A couple of us spoke about this the other day and decided that we would
> > take the following approach to sizing VMs on altarch hardware: 
> > 
> > Our Openstack instance, CICO Cloud, has the following VM sizes
> > available:
> > 
> >  Name   |  RAM | Disk | Ephemeral | VCPUs |
> > --------+------+------+-----------+-------+
> >  tiny   | 1940 |   10 | 0         |     1 |
> >  small  | 3875 |   20 | 0         |     2 |
> >  medium | 7750 |   40 | 0         |     4 |
> > --------+------+------+-----------+-------+
> > 
> > We will duplicate the same sizes for Libvirt VMs on altarch hardware,
> > but in order to take advantage of the incredible memory density on
> > these machines, we'll be adding a few flavors for libvirt nodes -only-:
> > 
> >  Name         |  RAM  | Disk | Ephemeral | VCPUs |
> > --------------+-------+------+-----------+-------+
> >  lram.tiny    | 11444 |   10 | 0         |     4 |
> >  lram.small   | 15258 |   20 | 0         |     8 |
> >  xram.tiny    | 22888 |   10 | 0         |     4 |
> >  xram.small   | 38750 |   20 | 0         |     8 |
> >  xram.medium  | 77500 |   40 | 0         |    16 |
> > --------------+-------+------+-----------+-------+
> > 
> > The aarch64 kit will allow: tiny,small,medium,lram.tiny,lram.small
> > The ppc64le kit will allow: all that you see above
> > 
> > What I'd like from you all is comments about the {l,x}ram sizing. We
> > have enough capacity to host quite a few of these VMs. Since this is
> > easy to change and we haven't opened this up to users yet, I'll continue
> > working on the provisioning side with this scheme in mind.
> > 
> > Cheers!
> > 
> > --
> > Brian 
> > 
> 
> Well, I don't see why we should go "insane" with the xram.* flavors.
> Actually in CI we only serve bare-metal nodes (as while it was mentioned
> multiple times that there is CI cloud, CI users aren't able -yet- to
> consume those instances, but that's another story) and forr bare-metal,
> depending on which nodes/chassis they get back, it's either 16Gb or
> 32Gb. so my point is that we shouldn't go higher than that, at least for
> the beginning.

We can remove the medium for now, but there's nothing constraining us to
32G hardware either for the moment (besides what's currently deployed). 

> 
> I don't know when (for example) RDO will be able to test a deployment in
> CI, but for sure they'll probably have other needs than vcpus/memory, as
> they'll have a need for storage (and bigger than 40Gb ?)
> 

Disks are another story, we could almost double the disk on the lram and
xram flavors and still be ok capacity-wise I think, but we'll need to
gather usage patterns down the line.