A Month with a Mac: A Die-Hard PC User's Perspective

OS X Bottlenecks and Caching

Although the performance of OS X on the dual 2GHz G5 system that I'd been running was definitely acceptable, there is definitely room for improvement. The overall responsiveness of the system was decent, but go back to using a top-of-the-line PC in Windows for a few minutes, and you definitely feel a bit sluggish on the G5. I would say honestly that a 3GHz G5 would be a good speed to have; although, I have yet to try out the new 2.5GHz G5s to see how much things have improved with a 25% increase in clock speed.

I've already mentioned video memory as being a bottleneck under OS X, thanks to the OpenGL accelerated UI. But luckily, with a more expensive video card (note: it's a shame that even a $3000 G5 comes with a measly ATI Radeon 9600 - shame on you Apple), that problem can be resolved; although, only through the expenditure of more money. There are, however, other performance related issues to which I have not been able to find solutions, even through faster hardware, which is definitely disappointing. The biggest issue seems to be scroll speed under OS X. Scrolling through any sort of window is much faster under Windows than it is under OS X. Take a browser window for example. If there's any flash running on the page and you try to scroll, you'll be greeted with a decently fast, but stuttering, scroll. It's almost as if saran wrap is behind each and every Finder window just to make things interesting. Regardless of what causes it, it's annoying - but thanks to how nice and polished the rest of OS X is, it's something that can be ignored. It does get frustrating at times, but it's one of those things that I'm able to live with, surprisingly. I think that I'm beginning to understand much of Apple's user base.

Performance isn't always a negative thing under OS X. In fact, there is one aspect of OS X's performance that I do believe significantly outshines that of even Windows XP: caching. The biggest pet peeve of mine as a PC user is hearing that hard drive crunch and having it be the reason for an interruption in my work, play or whatever else that I may be using my PC for at the time. I always get the upgrade-bug just as soon as I hear that drive crunch away, and immediately, I want to upgrade any and everything in my system to make those few seconds that feel like an eternity cease once and for all. Of course, regardless of how much I throw at the problem, it's always there and although I can lessen it, I cannot rid myself of it.

What I found in my time with the G5 and OS X was that it does a marvelous job of caching, to the point where after the first time I start the machine, I rarely hear the hard drive being accessed. Furthermore, I definitely don't feel as slowed down by it as I do under Windows. Again, I feel a bit lost writing this without a complete understanding of how Apple architected the caching system of OS X, but the results are positive and noticeable.

The obvious requirement for any OS that caches heavily is a lot of memory; while my system shipped with 512MB of memory, I quickly found the need to upgrade to more. At first, it was 2GB, then 4GB and I even contemplated going up to the 8GB limit; although, with 4GB, I definitely have memory to spare. What I found, however, was that unlike under Windows, the extra memory actually did something under OS X. The more room it had to cache, the more it spread its wings and the better it did. Obviously, there are limitations. For me, beyond 2GB wasn't really necessary (I was mostly testing out a set of 1GB modules that OCZ had sent) and even up to 2GB, I could've probably been fine with somewhere between 1 - 1.5GB without a change in the feel of the system. With enough memory, the I/O bottleneck that I had been used to dealing with for so long isn't gone, but significantly lessened on the Mac. This doesn't apply if you're doing anything I/O intensive, such as running a file server, database (to an extent) or video editing, but for a user like me, the difference is significant - and appreciated. In fact, I'd say that this is one of the things that kept me happy with the system for so long.