pvmanager is a client utility library to collect and process data in (soft) real-time. It allows to decouple the rate of events on the network from the rate of refresh needed by the client (typically UI) itself.
pvmanager is a part of DIIRT: Data Integration In Real-Time
To get started, look at the examples and documentation.
You can also browse Gabriele's old presentations. Be aware that some information may have changed from the time the slides were prepared.