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Profiles Panel

The Profiles panel lets you profile the execution time and memory usage of a web app or page. The Profiles panel includes two profilers: a CPU profiler and a Heap profiler. These help you to understand where resources are being spent, and so help you to optimize your code:

• The CPU profiler shows where execution time is spent in your page's JavaScript functions.
• The Heap profiler shows memory distribution by your page's JavaScript objects and related DOM nodes.
• The CSS Selector Profiler records the aggregate time spent matching selectors to elements in the DOM tree. This time is also captured within "Style Recalculation" Timeline events.