Dirty memory use in iOS

My app uses about 50 MB of memory at startup when I look at dirty memory using the VM Tracker instrument. It's a pretty simple app, an开发者_运维知识库d from what I recall at WWDC this year, this seems like way too much memory use for an app with only one simple UIWebview at startup.

I think I recall someone from Apple telling me to keep my memory use below 20MB as a guideline.

Before I go off and try to track this down - what's a good target to keep performance smooth and mem warnings reasonable?

Virtual Memory != RSIZE. Don't get confused. Virtual Memory includes all sorts of shared memory, including mapped files and frameworks. What you really care about keeping low is your resident memory (RSIZE).