react-native performance monitor

Question

This feels like a silly question, but what do the various numbers mean on react-native performance monitor? I haven't been able to find in the docs.

I understand RAM. What are the others? What do the two separate numbers mean for Views? Is that frames per second? What should I read to in order to become competent on how to use this tool? How reliable is this tool? What benchmarks should I be aiming for?

Answer 1

Thanks @diedu for posting a link (to a post, which has a comment w/ this youtube vid):

Here's a basic list of what each of those things represents.

• RAM: memory
• JSC: Javascript heap / memory. Will only be updated as garbage collection occurs.
• Views: Two numbers. Top number is the number of views on the screen and bottom is the total number of views in the component. Bottom number typically larger but usually indicates you have something that could be improved / refactored.
• UI: main frames per second
• JS (not pictured in Q): javascript frames per second. not rendering js but still good to monitor.

Hope this helps someone.