On 12 4 2005 at 6:25 pm -0400, Steve Abrahamson wrote: >You don't think there'd be some overhead associated with managing 1,600+ >fragments, do you? Nah.
I am not a hardware engineer (disk drive designer) nor a low-level filesystem developer, but I again caution against getting too up in arms about this number. Perhaps if you had a very slow hard disk and if PM had to read in the entire database sequentially every time it did something, I would be concerned about it as well. But that is not the case. >I decided that the Finder might be smarter about laying a file down than >any app would likely be, so I did a simple Finder copy of the new >compacted database. 400+. Copied again. 250+. I went with that one, and >indeed, PM got noticeably better, but not for long; within a day it'd >started to lag again. > >So the Finder seems to have some better inside knowledge of disk usage, There is no way you can make that deduction based on the evidence you described. The Finder is merely a (somewhat crappy) graphical shell. I would be extremely surprised to learn that it had any particular "knowledge" about the underlying filesystems it uses. (In fact, since you can deal with a number of different filesystems, I posit the opposite). So, you copied a file a number of times and it ended up in fewer fragments. That's all you know. Now, to a question: How much free space do you have on your disk? My guess is not much...? >every day - of course it's going to be the most fragmented thing there. >It's got exponentially more writes than any other file, and that's >perfectly expected use. Sure, but there's also lots of caching going on (particularly with the overviews, message headers, etc.). >Should a mail app be expected to take more responsibility than other apps >for the state of it's file? Can it? I don't know either, but it's an >interesting question, at least. Maybe, but again, I'm not sure that this is relevant at all to your performance problems. Here's another question: How much RAM do you have, and how much is free? Open a terminal window, type "top", hit control-C, and copy the first 6 lines of the screen into a message here. I bet your disk is full and your RAM is in high contention so that your system is thrashing a lot of VM. -ben -- Ben Kennedy, chief magician zygoat creative technical services 613-228-3392 | 1-866-466-4628 http://www.zygoat.ca
