Virtual Box 5 and Windows 8.1 VM

[nickuk]

Hi there,
I've been a very happy yosemite 10.10.4 mac user, with virtual box 4.2.8.

I've installed Virtual box 5 and now the windows vm refuses to do much once its started, I see this error Dpc Watchdog Violation.

I've installed guest additions but to no avail, any hints or tips from anyone are greatfully received.

cheers,
Nick

[loukingjr]

Do you really mean VB 4.2.8? That is over 2 years old and there have been multiple updates since.

At any rate, attach the vbox.log (compressed) for your guest here in a message.

[nickuk]

Thank you for your reply.

I did of course mean virtual box 4.3.28 (it was rather late when I posted - apologies)

I've downgraded to 4.3.30 and my Windows 8.1 VM is working again.

I've attached my log for interest.

In essence I launched VB 5 on my Macbook pro that runs Yosemit 10.10.4, when i launch the windows VM it launches (seemingly using a lot more power than usual ), I log into windows, then it seems to freeze. The screen looks the same but when trying to resize the error flickers "Dpc Watchdog Violation". This is of course a window error. I installed the additions onto the windows vm and it made no difference.

Any help appreciated.

kind regards,
Nick

[loukingjr]

To be honest I don't know why your guest runs on 4.3.28 either. You have 8 CPUs assigned to the guest and your CPU only has 4 cores.

00:00:00.896959 NumCPUs <integer> = 0x0000000000000008 (8)

It should be set to 2 CPUs.
You also have the RAM set to 8GB which is most of your available memory. That is normally a problem.

00:00:00.839042 Host RAM: 16384MB total, 12091MB available
00:00:00.896962 RamSize <integer> = 0x0000000200000000 (8 589 934 592, 8 GB)

If you want to try VB 5.0 again, I would try more reasonable settings for the guest.

[nickuk]

Excellent spot!

I knew I was using half of the system RAM, but I wasn't sure of the cores I had available.

Looking at my system info this is what it tells me. Interestingly when I was setting the Processors for the VM it would let me select up to 8. Even though looking at the spec below I have four cores the VB 4.3.28/30 interface wouldn't complain until I'd selected more than 8....

Thank you again, I'll try it again now.

Model Name: MacBook Pro
Model Identifier: MacBookPro11,3
Processor Name: Intel Core i7
Processor Speed: 2.5 GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 6 MB
Memory: 16 GB

[nickuk]

Just read this which might explain the 8 cores...

"Hyper Threading" -- which allows the system to recognize eight total "cores" or "threads" (four real and four virtual). Still its too many to give to the VM. Win 8.1 ran very well with it on 4.3.28/30

[loukingjr]

VirtualBox only cares about cores and not threads. Personally I don't run guests with more than 2 CPUs and 2048MB of RAM and I have 32GBs of RAM on the host. That includes my Windows 8.1 guest.

[loukingjr]

Win 8.1 ran very well with it on 4.3.28/30

I have no idea how or why.

[nickuk]

I cannot thank you enough for your help. Its working again now. Clearly 4.3.x was being kind and overlooking my stupidity.

Thanks,
Nick