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.

What you want is what you get Stability
Comments Locked

215 Comments

View All Comments

  • dmr9748 - Saturday, October 9, 2004 - link

    You again failed to provide proof. The first site is a bunch of pictures. I have been to that campus and have met some of the people in those pictures. This is how funding works, if someone gives you money and says that you can only spend it on x, are you going to give up that funding? NO

    Now, let's take a look at comparing 2 exact same items. They will never perform the same. Do you know why? There is about a billion reasons why. The mos striaght and to the point example is the movie "Timeline." Look at post #97.

    The only one that came close to proving me wrong was the linuxsinder.com post. Problem is, he doesnt tell me what vendor he is going to except for dell and the things is I just did a price comparison on both those items. I have given the direct links to the vendors.

    With some of the last links you posted, go back to post #112.
  • rxmz - Saturday, October 9, 2004 - link

    Azkman has already answered #112 very well, but just a quick look at the Dell shows it only has 2 HD bays, neither front accessible nor hot swappable. It's not 64-bit, and doesn't have a 1GHz front-side bus. I'd guess there are other reasons it's not in the same comparison class as the Xserve G5, but I think that's plenty already.
  • azkman - Saturday, October 9, 2004 - link

    Hard evidence for #112 (none from pro-apple sources):

    http://www.tcf.vt.edu/systemX.html
    http://www.colsa.com/cover_page/news_front/news_de...
    http://www.top500.org/list/2003/11/
    http://www.linuxinsider.com/story/36120.html
    http://www.linuxinsider.com/story/36964.html
    http://www.roanoke.com/news/roanoke%5C6133.html
    http://www.pcmag.com/review/0%2C2491%2Cs%3D1564&am...
    http://www.pcmag.com/article2/0,1759,1369037,00.as...

    Specs do not equal performance. I haven't heard of any Dell supercomputers being built at breakthrough prices. I'd believe the jugdement and results of VT and the US Army over an arbitrary price comparison any day.
  • dmr9748 - Saturday, October 9, 2004 - link

    I just did a price comparison of my own between an xserve and a dell server.

    Here is the xserve for $2898.99

    http://www.ctistore.com/Merchant2/merchant.mvc?Scr...

    I priced a rackmount server with the same specs on dell.com for $2021

    http://configure.us.dell.com/dellstore/config.aspx...

    #95 Don't post an article that explains one system and then say it is more cost effective for what you get compared to another system when the article doesn't even mention a price for the system they are describing. Do not attack my post unless you have some hard evidence.

  • kmmatney - Saturday, October 9, 2004 - link

    reading all these comments from (most) the mac users that have posted makes me want a mac less and less.

    -- I second that one. $2500 for a computer with no monitor and a crap video card. That's the "uncomfortable" part to me.
  • victorpanlilio - Saturday, October 9, 2004 - link

    #109 dextrous wrote: reading all these comments from (most) the mac users that have posted makes me want a mac less and less.

    Care to elaborate? Using this same sort of reasoning, then all of the positive comments a people might happen to make about their own country should dissuade foreign tourists from visiting. And of course, such people should not object if their country is portrayed in a bad light by foreigners who know little or nothing about the country. What's more, the foreigners are afraid that a learning experience might actually force them to rethink their prejudices. To bring this discussion back on topic, what Anand has done is the equivalent of visiting a foreign country, sampling its cuisine, experiencing something of its culture, and so on. His "travelogue" describes his impressions. The forum participants chime in with their own dispatches from the field -- and those who have visited and perhaps lived in the foreign country for some time are in a better position to comment knowledgeably.
  • dextrous - Saturday, October 9, 2004 - link

    reading all these comments from (most) the mac users that have posted makes me want a mac less and less.
  • victorpanlilio - Saturday, October 9, 2004 - link

    In #107 topcat903 wrote: "Basically, this article describes the "uncomfortable" feeling we get when we switch to something we are not used to."

    And if that's all it was, then the remedy is simple -- learn. But in the article, as well as in the comments, uncalled-for remarks about price etc. detract from the overall message that it is quite possible for a diehard but open-minded Windows PC user to discover genuinely superior things about MacOS X even without delving into applications that make best use of the platform.
  • topcat903 - Saturday, October 9, 2004 - link

    I don't think this article was to compare which system (hardware or software wise) is better. It was written to describe the "experience" one would feel when switching to another OS (heck, the same thing could be said about switching girlfriends or boyfriends).

    I started my computing days using the Apple IIe, then the first Mac...eventually I switched to the Windows platform, and recently since my wife got an iBook, I had to switch back to OS X.

    Basically, this article describles the "uncomfortable" feeling we get when we switch to something we are not used to...A feeling I experienced many times over. All the speed, power, and storage of a system could mean nothing to me if I don't know all the ins and outs of what I'm using to get what I needed done.

    Overall, the article was a good and interesting read...just wish there was more on the audio/video apps (where Apple truly excel), however I assume it's not what the author's primary use of the G5...but hopefully a start towards many more articles.
  • rxmz - Saturday, October 9, 2004 - link

    A quick FYI semi-related to Mac OS X scroll speed. Clicking in the empty area of a scroll bar jumps by a page, but clicking while holding down the "option" key jumps straight to that point (reversible via a system preference). This comes in very handy for long documents (or file listings), when you know about where you're trying to go.

    As an aside, the only app I have seen where this does NOT work is MS Word....

Log in

Don't have an account? Sign up now