Dalvik cache takes 20 - 30 seconds to clear

[PPCGeeks4ME]

I recently noticed that my battery life is significantly worse than what I'm used to. Around the same time, I noticed that clearing the Dalvik cache now takes 20 - 30 seconds when it used to take only a few seconds. (If I clear it again immediately after clearing it I don't see this problem, obviously...but after a few days of usage the Dalvik cache gets really big again.)

I'm wondering if this could be a sign of problems. This has persisted over multiple ROM, radio, kernel, and PRI flashes. I have not tried installing apps one-by-one to see which is causing the problem, because that would take a while. Is the always-full Davlik cache a clue that could help me find what's hogging the battery?

Or maybe my battery is just getting older, and the Davlik cache thing is the result of a new feature in one of the new updates. I don't remember my exact flash history, but right now my software history says (ignore sig, I haven't updated it):

Android 2.2
Baseband 2.15.00.11.19
Kernel 2.6.32.27-netarchy-toastmod-4.3-cfs-havs-more-sbc
Build MikFroYo v4.1 - Logical Sense
Software 3.70.651.1
Browser WebKit 3.1
PRI 1.90_003
PRL 60674

I've changed all of those things except Android and Browser since I first noticed the Dalvik issue and poor battery life. My hardware revision is 003.

Thanks to anyone who can help me better understand this issue.