Mailing List Archived Message #174

From: "Doug Bissett" <> Full Headers
Undecoded message
Subject: Re: [Virtualized eCS] Vbox question and cores (AOS 503)
Date: Fri, 10 Dec 2021 10:20:10 -0700 (MST)
To: "Virtualized eCS Users Mailing List" <>

On 2021-12-10, at 15:04:59, Massimo S. wrote:
> Il 09/12/2021 21:16, Doug Bissett ha scritto:
> >On 2021-12-09, at 20:20:28, Massimo S. wrote:
> >>
> >>Hi all,
> >>
> >>is it possible to give 3 or 5 cores to an AOS503 guest VM?
> >>
> >>thanks
> >>
> >>massimo
> >Yes.  AFAIK, you can use up to the number of real cores. HOWEVER, using more than one core will cause problems,
> why?
> never had one with ACPI
> my production servers use 1, 2 or 4 cores, i never had one hang or trap
> >and it will likely not make much difference in performance (it makes very little difference when running a XP, or win 7,
> guests).
> no, sorry, they do if you are using real world production servers
> >>From what I see, VBox uses support similar to Hyper Threading, and Hyper Threading is not very friendly to OS/2.
> >Try it, and see what happens. I suspect that it will hang after a short period. I haven't tried it for a couple of years, something
> may have changed (but I doubt it).
> my production servers use 1, 2 or 4 cores, i never had a trap or hang or whatever
> my only doubt was MP (3,5,7) not SMP number of cores
> you didn't try that
> ok, thanks anyway
> massimo

I think you misunderstood. The VBox HOST can run under any number of cores (including Hyper Threading). Using the setting in VBox to use more than one core for an OS/2 GUEST will cause trouble because VBox seems to use the same thing that Hyper Threading uses. Hyper Threading is not completely compatible with the OS/2 job scheduler, and it will, cause OS/2 to hang, eventually (usually sooner, than later).

My comments about XP and 7, were about using multiple processors in the GUEST. It makes very little difference over running them with a single processor configured, but that may depend on exactly what you are doing with them.

From Doug Bissett's ArcaOS system
dougb007 AT
... PROGRAM: n. used to turn valid data into error messages

Subscribe: Feed, Digest, Index.
Mail to ListMaster