Hanging when 3 VMs are running on Windows 7 x64 host

[Ihor Bobak]

I have 3 virtual machines:

• Windows 2003 Enterprise x64
• Windows 2003 Enterprise x86
• FreeBSD x86

All of them were originally created by VirtualBox (they are not imported from VHD or something like this).

The host is Windows 7 x64 - this is HP Pavilion dv7 (Processor Intel(R) Core(TM)2 Duo CPU P8600 @ 2.40GHz, 4 GB of memory, 2x250 GB hard drives)

As soon as I run all 3 virtual machine all together - my host machine becomes not responsive: the keyboard and mouse do not react on pressing/movement, processor goes up (I hear how the fans are working hard), and it hangs for an hour until I simply press power off.

If I run only 2 of them (any 2 of them) - everything is fine.

I feel that virtual box simply cannot run more than 2 guests simultaneously. I had such situations previously with other 3 machines - as soon as I've launched the 3rd one - everything hanged.

Can anyone suggest me, what should I do (maybe to unplug some option in the settings?) in order to force all 3 VMs working?

When I had VMWare Workstation, I could run even 4 guests on this PC - everything was fine and there were no such problems.

Thanks in advance. Ihor.

Note: the amount of memory which they consume in total is 3GB, while I have 4GB in my system. So everything is fine with that.

[Sander van Leeuwen]

You can run as many guests as RAM allows for. It's unwise to assign 3 GB to VMs when you only have 4 GB. How do you come up with the 3 GB number? Did you just add the RAM for all 3 VMs? Note that more is required than that (VRAM + virtualization overhead).

Keep in mind that all memory required by the VMs is locked and never released (VMWare handles it differently; we will too in a future version)

Sounds to me like a simple case of running out of memory. Any component in the system can cause a fatal problem then.