VMware blames Apple for Fusion corruption

Stephen Withers
Monday, 21 July 2008 04:57

Business IT - Technology

It seems that unbuffered I/O is still failing in some circumstances when used by Fusion. If the bug causes the virtual machine to hang at the wrong time (not that there's ever a right time for a hang!), its disk can become corrupted to the extent that the guest operating system must be reinstalled or the VM image restored from a (hopefully recent) backup.

For now, VMware says "We have reported this issue to Apple, but until this bug is resolved, we recommend that all VMware Fusion users ensure they select the default option, in VMware Fusion Preferences, for 'Optimize for virtual machine disk performance' to guard against potential data loss."

Fusion was released about a year ago. Like Parallels Desktop, it allows the creation of virtual machines that can be used to run other operating systems such as Windows or Linux.

While Mac OS X's Boot Camp feature allows dual booting of Mac OS X or Windows, it can be more convenient to run guest operating systems on virtual machines as this makes it quicker to switch between OSes and simplifies the exchange of information between applications running on different OSes.

One downside is that applications run more slowly under a guest OS, though this may not be significant depending on their nature. For example, a Mac-based web developer may be more concerned about how pages are rendered by Internet Explorer, but speed is far more important when playing games.