Running new app in pwb hangs VirtualBox

[adakasty]

Hello

I'm rather new user of VirtualBox (only few weeks). My host system is ubuntu 9.04, VirtualBox version is 3.0.4, guest is Windows XP with SP3 (and is rather fully updated). I've got some work on assembler for DOS and win32 to do, so my first decision was to try running it on VM. On my university we used pwb (Programmer's WorkBench) to see what programming in asm looked like, so I tried using it on VM. Everything worked fine - compiling, building, debugging... but one thing. When i tried simply executing the simple program from within pwb, the VM hanged. At first i thought it's just some OS lag, but after trying to pause / send ACPI / close it, the window stopped responding. The same when I was trying pausing the machine from the machine manager. After killing the windows by pressing "X" button at windows... VirtualBox process was still working and using up whole core of my CPU. Killing the process helped.
This was what happened. I've tried to repeat same thing multiple times on the same machine, every time same thing happened.
Some info that might be helpful: CPU is Pentium 4 (prescott) with HT, I'm working on 1 cpu in VirtualBox with PAE. CPU doesn't support any hardware virtualisation.
PWB is very greedy for resources - even that it's just console app (it uses up all free CPU time while idle)
Fortunately for me PWB works well on DosBox so I can do my work with it... but maybe there's something in VirtualBox that I could help improving

adakasty

[mpack]

I take it PWB is a 16 bit development environment?

VBox virtualisation does not work well with 16bit apps. I too have had VBox lockups when a 16bit program running in the VM goes a bit off rails.

Is your host CPU a dual core or better?

[adakasty]

Oh, that explains a lot. Yes, PWB is for developing 16bit applications. My host CPU is one core Pentium 4 (prescott) with Hyper Threading, so it behaves like it's dual core (OS thinks it's dual core), but performance is about 130% of one core.
I was worried that something was wrong and there would be problems with creating normal apps... so I am relieved