Improve UI performance

[john-hu]

We use main-thread to handle all messages from websocket. It would be nice to handle the data at batch. Because the message from web worker may be too fast that a redux cannot handle it with clone or immutable structure. We can aggregate some of them and process them in a batch.

[kilikkuo]

By setting a timeout for those tasks which send data to browser via websocket [1], it improved the UI response time.
To handle those tasks in a batch would be a good next step !

[1] cc12176#diff-6a65a002c0884542424d32c1a57310d2R373