Re: CPU hot-plug and RAM hot-add in virtual machines

From: Miroslav Lachman <>
Date: Wed, 21 Jul 2021 12:06:07 UTC
On 21/07/2021 11:58, Rainer Duffner wrote:

> My guess is that it’s something that is very much tied to the Linux kernel.
> AFAIK, it works on RHEL (and derivatives), and that’s usually a sign that it’s 100% tied to the Linux-kernel.
> We have over 20 Vcenters (yeah...) with thousands of VMs and AFAIK, only one customer has ever requested that feature.
> Do you really need it that badly?

Thank you for the insights.
I don't need that badly but it is another problem our customers have 
with FreeBSD over Linux. One of them has about 50 VM, mostly Linux, some 
Windows and 8 FreeBSD. I maintain the FreeBSD VMs. They need to add RAM 
and CPU often because of the growth of their projects and as they do not 
like maintenance downtimes they are happy with hot add and hot plug on 
Linux VMs and were kind of disappointed that FreeBSD does not support it.
No body will leave FreeBSD just because of that but when somebody counts 
problems with this, with ElasticSearch, some NPM / Yarn packages, 
popularity of Docker and so on, then they ask "Why not migrate all to 

Kind regards
Miroslav Lachman