Clark's Tech Blog

I’m not running the betas of Snow Leopard but I’ve heard from a lot of people that while there aren’t a lot of new end user features or UI changes that it is considerably speedier. One question some have is over device drivers.

Snow Leopard runs in two kernel modes. 64bit and 32bit. To ensure device driver compatibility it runs in 32bit kernel mode but allows full 64bit applications to run. However, at least in the betas, you can run in full 64bit mode by holding down the 6 and 4 keys. (Get it?) Alternatively you can add arch=x86_64 to your boot.plist. (If you have to ask where it is you probably shouldn’t be changing it)

Want to know which device drivers are 32bit? Well chances are if you are running a 3rd party device driver it’s 32bit. There’s a command to list them though: kextstat

If the output starts with com.apple it will be 64bit under Snow Leopard.

Here’s a few of my non-Apple device drivers:

com.google.filesystems.fusefs This is Google’s excellent fusefs which allow you to read NTSF files. You can also do cool things like mount FTP points.

com.parallels.kext.* There are a bunch These are for Parallels, which I use to run Windows at times.

com.baltaks.driver.DoubleCommand This is a nice little program that customizes some features of the keyboard.

com.Logitech.Control Center.HID Driver This is for all those extra mouse buttons on my Logitech mouse. I need to switch to a different app one of these days because this is the cause of most of my crashes.

I could do without DoubleCommand. Any alternative to my LCC driver would probably have the same problem and I love having those mouse buttons tied to Spaces and Expose. I use them constantly and they are a big part of my workflow. But not being able to run Windows would be a deal breaker for me.

I suspect we’ll see some updates soon after Snow Leopard is released though. At which point I’ll have to decide whether to convert to VMWare or upgrade to the new version of Parallels.

Related posts:

1. List Your Non-Apple Kernel Extensions
2. Upgrading to Snow Leopard Part 6: 64bit vs. 32bit
3. Complaining about Snow Leopard
4. Upgrading to Snow Leopard Part 7: One Month Later
5. Upgrading to Snow Leopard Part 2: Minor Tips
6. Limit 64 bit apps to Snow Leopard
7. Microsoft Mouse Drivers
8. Upgrading to Snow Leopard Part 5: The Python Gripes