For example, will low disk space cause Chrome to clear the cache? Or will it simply stop caching new files, or maybe clear the files least recently used?
By default - any cache associated with active sessions that expire on browser close will be cleared with the close down of chrome.
Any content set to not cache by the web server (meta tags) will get dropped on page/domain change.
Chrome cache will overwrite itself when your cache gets full. This is (if memory serves) 1GB by default but can be set by using the chrome command line command "
You can check your current chrome cache values by browsing to