Ping time rate

Could you please what is best ping time rate between elastic search vm and application?

Best for what?

I meed to know the ping time rate between app and es to avoid latency and delay

The best ping time is as small as possible.
Anything over a second might be a bit too slow, but it's too hard to say without more information on what you are doing.

thanks , i ping from app to elastic by 1 ms . Is this good or may cause a delay?

It'll cause a delay of 1ms, which is pretty good!