What is React native's "JSTimers.callTimers"?

Question

I'm debugging the react-native bridge to see conversations between native & JS side.

As I can see so many messages were sent via the bridge even I didn't touch anything, it's a non-stop conversation.

method: "callTimers" module: "JSTimers" type: 0

args: (4) [(...), (...), (...), (...)] method: "createTimer" module: "Timing" type: 1

args: [(...)] method: "deleteTimer" module: "Timing" type: 1

Can anyone explain this issue to me?

Here how I inspect the bridge messages:

  import MessageQueue from 'react-native/Libraries/BatchedBridge/MessageQueue';

  MessageQueue.spy((msg) => {
      const fromTo = msg.type === 0 ? '[To JS]' : '[To Native]';
      const color = msg.type === 0 ? '#693' : '#639';
      console.log('%c' + fromTo + ' args, msg:', 'color: ' + color, msg.args, msg)
  })