mitchellh/vagrant — Issue #565: VirtualBox FLUSH CACHE I/O issue
Author: zimbatm
Created: 2011-11-21 20:35:25+00:00
State: open

I know this is a Virtualbox issue but if we can find a work-around it would be nice.

The problem: when a lot of IO happens, like apt-get installs, the system slows down a lot. After a while, the linux guest machine starts to issue FLUSH CACHE kernel errors if you have the GUI. If you keep up, the linux guest re-mounts / as read-only. Then finally it crashes my OSX host machine. That makes Vagrant not really usable for Chef cookbooks testing.

By default Virtualbox doesn't forward the flush command to the OS. I suspect it causes write bursts which makes things really slow. It's actually possible to change that behavior ( http://www.virtualbox.org/manual/ch12.html -> "Responding to guest IDE/SATA flush requests" ) so I'm investigating to change that. Maybe pre-allocating the VM image would solve the issue as well.