I've been running Chrome with memory profiling enabled. I started with a gmail tab that I used for ~2 weeks. Then I forced a GC, navigated to about:blank, and then forced another GC. The renderer that was hosting the about:blank frame still has ~6 thousand feature providers that have not been destroyed. These stats come from a renderer that is only hosting about:blank.

Raw & processed data: https://bugs.chromium.org/p/chromium/issues/detail?id=733323#c2
Methodology: https://docs.google.com/document/d/1fN5balfyrd7sRpd6DRaUI1TwoOwYjLyRSd7mwZT5US8/edit#

Each screenshot shows:
  1) # of objects created [that have not been destroyed]
  2) The stack trace of the code that created the object.

1) This seems like a large number of feature providers to have around...maybe an issue with the caching logic?
2) I don't think we still need this many feature providers after hitting about:blank, right? Maybe we should try to clear the cache at reasonable points in time?
 

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