Comment 2 for bug 1728256

Unfortunately I have bad news, but I also have (kind of) good news.
Bad news is, 2.9 is NOT stable, contrary to what I believed earlier.
Good news is, I found a correlation between the crashes and converting large video files on an SMB share with ffmpeg, so effectively copying slowly with simultaneously high CPU load. In that constellation it crashed a few times after just hours (instead of days sometimes). I suspect it might be a network related issue. I am now testing the different virtual network hardware that qemu supports (which proved to be difficult due to lack of driver support in Windows).

On that note, I remember right after setting up the VM I had some strange networking related hangup issues with the rtl8139 virtual adapter - the default -, where the VM would slowly grind to a complete halt over a few seconds when I started a very network-heavy task (like copying something from the host via SMB into the VM). I could prevent the hang when I paused the copying for a few seconds. At that time I assumed it was the hardware registering as 100Mbps adapter, but the actual load being about 4 times that on average (during copying of course), with peaks significantly higher (about 15-20 times). That issue completely went away after switching the virtual network hardware to virtio (which registers as 10Gbps adapter), and I considered that case closed.