title: Do I need a lock on a list where I add or remove object from list on invocation of signalR hub?
body: <p>I'm currently working on an app where players can enter a tournament to play and there are no limitations on how many players can play the same tournament. Players are using React.js client with signalR and they are invoking the hub method for registration and unregistration. For player storage, I use in a tournament object a List so when a player is registered in a tournament it is added to a list and when is unregistered it is removed form the list in two different methods.
  Do I need a lock and how should it be implemented?</p>