Archive for May 16, 2006

Tuesday, May 16, 2006

OS Speed

Peter Ammon:

Now, when allocating memory, malloc can either manage the memory blocks on the application heap, or it can go to the kernel’s virtual memory system for fresh pages. The application heap is faster because it does not require a round trip to the kernel, but some allocation patterns can cause "holes" in the heap, which waste memory and ultimately hurt performance. If the allocation is performed by the kernel, then the kernel can defragment the pages and avoid wasting memory.

Because most programmers understand that large allocations are expensive, and larger allocations produce more fragmentation, Windows, Linux, and Mac OS X will all switch over from heap-managed allocations to VM-managed allocations at a certain size. That size is determined by the malloc implementation.

Dastardly Dialogs

I ran into this dialog on Sunday and assumed it was referring to a PowerPC pref pane. But the only third-party pref pane I had was Growl, and it was already Universal. Nevertheless, I re-installed the exact same version, and it proceeded to work.

Now, On Intel

With NetNewsWire now Universal and PyObjC working more reliably on Intel, I finally switched over to the iMac as my main machine. As expected, it screams, especially for compiling.

I was using two Dell 2005FPWs with the G5, so now I have one attached to the iMac. So far, I haven’t quite been able to get the colors on the Dell and the internal display to match. The internal display is actually brighter than the Dell, which is amazing since last year the Dell was significantly brighter than any LCD I’d ever seen. The Dell case is hideous, of course, but I find its picture slightly easier on the eyes. Oddly, the iMac, contra the G5, can’t seem to put the Dell to sleep. Instead of turning it off, it puts it into a self-test feature check mode, showing some RGBW color bars floating around on a black background.

I reiterate my opinion that the iMac Core Duo is one of Apple’s best-ever machines. At this point, I mainly wish that its optical driver were faster and that it had two headphone ports like the original iMac.

CDFinder 4.6

CDFinder, my favorite disk cataloger is now Universal and has a slightly more Aqua appearance and more powerful searching.

MacBook

Given Apple’s recent hardware updates, the MacBook is pretty much what you’d expect. MagSafe. Front Row. The base model costs $100 more than the iBook. Core Duo. AirPort and Bluetooth are built-in, but the modem is optional and external. Dual-display support with DVI out, but integrated video. The 1280x800 display is wider (and brighter), and the computer itself is wider and thinner.

What I didn’t expect: There’s no Core Solo model for $999. It’s 0.3 pounds heavier than the 12-inch iBook and 0.6 pounds heaver than the 12-inch PowerBook. When configured identically, it costs $150 extra to get the black. [Update: And, apparently, there’s no microphone. Weird. Update 2: Unlike the G4 iBook and PowerBook, the MacBook and MacBook Pro have power adapters with different wattages.] Some people are grumbling that at about 1.6 inches wider than the iBook it’s too large (even though the other two dimensions are smaller), but I think it’s a reasonable trade for the additional pixels. Overall, a great machine, especially for students. I would’t be surprised if Apple can’t meet demand for these things.