Comment # 16 on bug 1207807 from Vlastimil Babka

(In reply to Alexander Krupp from comment #14)
> However, I do not know whether VMWare is the only (virtualization) software
> affected by this. If this affects more software and users, it may make sense

I haven't heard of others than vmware. Certainly if it was affecting kvm or xen
the same way, we would have heard and debugged that in upstream.

(In reply to Alexander Krupp from comment #15)
> RH disables compaction by default
> 
> https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/
> html/8.4_release_notes/kernel_parameters_changes
> 
> Found this while reading up on what this parameter does.
> 
> I vote for the "principle of least surprise". As did RH.

But the important details is that this is for RHEL 8.4 with a kernel based
AFAICS on 4.18, where upstream proactive compaction was merged later than that.
Which suggests they backported the feature between 8.3 and 8.4 and in a minor
service pack not updating the whole kernel, the principle of least surprise may
indeed be important. If the feature comes with a new upstream kernel, usually
the defaults are used unless there's a known problem.