Re: VMD more than one vCPU per VM and 4+ VMs running simultaneously

On Tuesday, July 29th, 2025 at 7:34 PM, Mike Larkin <mlarkin@nested.page> wrote:

> On Tue, Jul 29, 2025 at 07:08:16AM +0000, Martin wrote:
>
> > Mike, does real interrupt controller implemented in vmd already? It should significantly improve the performance of the vmd by allowing real hardclock interrupts which significantly reduce CPU usage.
>
>
> vmd emulates a legacy i8259 and i8253 for irq routing and clock gen.
>

vmm_clock helps to track clocking with Linux kernel based host system. Works fine once kernel module has been installed.

> you can use pvclock or vmm_clock if you want better clocking in guests until
> something like an hpet or acpitimer is implemented.
>
> > More vCPUs per VM moves vmd to the near one level of commercial hypervisors but better in many cases and much simpler configured.
>

It will be better if it sound like a plan. Very helpful feature.

>
> agree
>
> > On Monday, July 28th, 2025 at 7:30 PM, Mike Larkin mlarkin@nested.page wrote:
> >
> > > On Mon, Jul 28, 2025 at 03:27:15PM +0000, Martin wrote:
> > >
> > > > On Monday, July 28th, 2025 at 12:11 PM, Mike Larkin mlarkin@nested.page wrote:
> > > >
> > > > > On Mon, Jul 28, 2025 at 06:06:46AM +0000, Martin wrote:
> > > > >
> > > > > > Hi list!
> > > > > >
> > > > > > More than one vCPU per VM is implemented/planned?
> > > >
> > > > It is really good idea to have more than one vCPU per VM. vmd looks stable enough from 7.7 as I can test in many production cases. Maybe try to add some multi vCPU feature next?
> > >
> > > good idea
> > >
> > > > > not implemented as of now.
> > > > >
> > > > > > Can anybody share some way how to increase VM quantity per host (more than four VMs running simultaneously) if host has CPU with 16 kernels and 32 threads or more?
> > > >
> > > > Just add mote /dev/tapX interfaces to increase VM count running on my hosts. Host RAM is enougth to run 16+ VMs simultaneously for now.
> > >
> > > makes sense
> > >
> > > > > I don't know what this means. You can have as many VMs running as you want.
> > > > > The constraint is host RAM vs the memory assigned to each VM.
> > > > >
> > > > > > Thanks.
> > > > > >
> > > > > > Martin