getting old
That's just how it works. The software scans your entire library, the only way to avoid that is by hacking it to hide some of your music. Sure, it's possible to test on a few songs but saying that without explanation makes it sound like you either don't understand how the service works, or you didn't really test it out.
look, this is getting old. If I didn't state previously (I thought I did), then I will state again: I used LAME in the late 90s to convert most of my favorite tunes to mp3 (192, 256 and 320vbr). Tagging is probably minimal due to tagging always being somewhat hit or miss. If iTunes is matching based on tagging, then I will later try to fiddle with my tags to see if that helps.
Finally, I'm not sure why people are so concerned what my library set up is. You know, if Itunes and iPhoto actually even allowed you to move files between different libraries, I might have a better setup. As it is, I have a mac mini with an external usb where I have (multiple) itunes and iphoto libraries -- but mostly 1 large library for each. So, what do I have in iTunes on my 1/2 a dozen other macs? NOTHING. So, you start up itunes, import a few test songs and test match. It's really not rocket science.
I forget which key it is -- holding option while launching? whatever -- you get to choose the library to use (and the app seems to remember for the next time). Finally, I found some software by some company (sleepy cat?) that seems to allow me to move music between libraries. $20 well spent for a feature that apple should be providing inherently.
Someone else said the failure is mine. Is it? it's my failure because the software works poorly for me? I guess that makes you feel better about yourself, whatever. Finally, I really just don't have a lot of time to (constantly be) upgrading and converting my music "library" ... I have old mp3s (again, that didn't come from napster or other places -- hell, they might even have worked better IF that had come from there since they would probably be tagged better... but they didn't) with probably questionable tagging. I know I have almost 0 cover art -- and that's probably based off tagging as well.
enough.
Scott