VM disk thrashing on Windows 10 host

[NickP]

I had VirtualBox running on Windows 8.1 x64 with a couple of Linux VMs, and performance was quite satisfactory. I recently upgraded the host to Windows 10, retaining apps and data, and since then I notice that running any update process in the VMs (eg sudo apt-get upgrade) results in continuous disk thrashing for many minutes on the host as the updates are being installed. For instance, I just installed some new kernel files in one of the VMs, and rather than the minute or two that the process took when the host was Windows 8.1, it now takes about 15 minutes, with the disk activity light hard on the entire time and the disk audibly thrashing. The problem happened both with VirtualBox 5.0.2, which was the version installed when I upgraded from Win8.1, and with the present 5.0.8. The VMs are adequately resourced - the host has 32Gb RAM and each VM has 8Gb RAM.

[Perryg]

What makes you think this is a VirtualBox issue and not a Windows one?

[NickP]

What makes you think this is a VirtualBox issue and not a Windows one?

Because:

1. The disk containing the VDI files (a WD Black 4Tb) holds only data. C: drive is a separate SSD, and the TEMP directory and paging file are on a second SSD. All drives have content indexing disabled.

2. The problem only happens when running Virtualbox and not when running any other application. Some of the other applications I use are quite disk-intensive - eg editing large images with Photoshop, and although these apps can cause heavy disk activity, it never persists for more than a few seconds. Only with Virtualbox does the disk activity persist for many minutes at a time.

[Perryg]

Still this is only speculation. What you need to do is show proof, and as you stated it worked in 8.1. It very well may be an issue with VirtualBox but as far as I know this has not been a reported problem with the exception of the Windows update and some aggressive virus scanners.

[loukingjr]

My two cents: I have no disk thrashing on my Windows 10 host and certainly no guest takes 15 minutes to update a kernel. I don't believe it's a VirtualBox issue either.

[mpack]

Speculation is fun, but a VM log file might be more productive.