Push-based update is a communication technique in which the server sends data when something meaningful changes, instead of waiting for repeated client requests. section 8.4.4
Polling versus push
A dashboard that polls every five seconds repeatedly asks whether anything changed, creating many wasted requests. When updates are frequent, WebSockets or Server-Sent Events can send changes only when needed. section 8.4.4
Choose push when frequent updates justify an open connection; choose modest polling when updates are rare and simplicity matters. Open connections still consume server resources. section 8.4.4
