Building Distributed Systems With Stateright

Stateright is a model checker for distributed systems. It is provided as a Rust library, and it allows you to verify systems implemented in Rust. It is openly available on GitHub and the developer, Jon Nadal, is looking for contributors and new users.  

On Tuesday Jon gave a presentation to us on Zoom. He made his presentation slides available here. We have also recorded Jon's presentation and the Q&A and demo sessions in entirety.

  

The highlights of Stateright are:

• great visualization support,
• time travel debugger: which helps you go back/forth and choose to explore another branch from a given point of the current execution (in the Figure below, the Next Steps heading provide possible next steps to choose from),
  
• an actor-based model,
• an embedded linearizability tester,
  
• and extensive docs and Rust book for introducing the concepts.

The model trait has state, init_states, actions, next_state, and properties.

Similarly there is an actor trait you can implement, and model check as follows.

The Rust book for Stateright gives examples of model checking ABD protocol in Rust and the chapter on Paxos protocol is coming soon. 

To improve the performance of model checking, the checker fingerprints states and digests states into 64 bit integers. Rust is also a fast language because it does not do much pointer hopping. Jon said he will try to implement dynamic partial order reduction to improve the performance of model checking further. The model checker is already parallel, but running on many machines in a distributed fashion can also be added.