09-05-2010, 11:04 AM

I received my new Macbook Pro on Friday and overall I've got to say I'm very impressed. It's going to take some getting used to but that's to be expected after almost 30 years of using PCs.

One thing I was surprised by though was the fact that Snow Leopard boots up in 32 bit mode by default on the Macbook Pro, so I figured I'd point that out to other folks switching over who might think their 64 bit machine will boot in 64 mode by default. I stumbled across the following article while doing some research on performance with Photoshop, so I checked my system using the steps outlined in the article and, sure enough, it was 32 bit.

Macintosh Performance Guide: Mac OS X 10.6 Snow Leopard: Booting the 64-bit Kernel

Perhaps this will change with the next upgrade of the Macbooks as it recently did with the Mac Pro line but, for now, it appears that you need to tell the system to boot in 64 bit.

09-05-2010, 11:10 AM

Just because 64-bit kernel and extensions isn't booted, doesn't mean your 64-bit software won't run in 64-bit mode.

There's a lot of great information about 64-bit mode here:

64-bit and Snow Leopard – What 64-bit means for you

09-05-2010, 11:22 AM

Originally Posted by cwa107

Just because 64-bit kernel and extensions isn't booted, doesn't mean your 64-bit software won't run in 64-bit mode.

Absolutely. Open up Activity Monitor (/Applications/Utilities/) and look at the "Kind" column. A quick glance will reveal how many applications are running as 64-bit applications.

09-05-2010, 11:32 AM

cwa107 - thanks for the link - lots of good info there! For me, any performance increase is worthwhile, so I'll give this a go for a while. There are some programs that I will need to run in 32 bit for the time being, such as Photoshop when using my Nik plugins, but that's easy enough to change back and forth.

09-05-2010, 11:35 AM

Originally Posted by vansmith

Absolutely. Open up Activity Monitor (/Applications/Utilities/) and look at the "Kind" column. A quick glance will reveal how many applications are running as 64-bit applications.

vansmith - thanks for that tip; I'll have to check that out the next time I reboot.

09-05-2010, 12:30 PM

Originally Posted by rfreschner

cwa107 - thanks for the link - lots of good info there! For me, any performance increase is worthwhile, so I'll give this a go for a while. There are some programs that I will need to run in 32 bit for the time being, such as Photoshop when using my Nik plugins, but that's easy enough to change back and forth.

Just to be clear, 64-bit doesn't always mean performance improvements. In fact, some software can actually suffer performance degradation.

I think for a lot of people who are children of the 80's (when console gaming was big and systems were referred to as 8-bit, 16-bit, etc), we tend to think that if 64-bit is twice as large as 32-bit, it must mean twice the performance. And that's simply not true.

Heavy hitter apps like Photoshop or anything particularly calculation intensive will see a boost from running in 64-bit mode. But again, nothing stops you from running a 64-bit app with the 32-bit kernel and extensions running, nor does it mean that the app will run slower.

09-05-2010, 12:39 PM

Originally Posted by cwa107

Just to be clear, 64-bit doesn't always mean performance improvements.

Heavy hitter apps like Photoshop or anything particularly calculation intensive will see a boost from running in 64-bit mode. But again, nothing stops you from running a 64-bit app with the 32-bit kernel and extensions running, nor does it mean that the app will run slower.

Agreed. From what I've read so far though, there is a performance boost running PS in the 64 bit kernel, but again this is what I've read, so I'll have to try it out to see for myself.