Re: [Libguestfs] [PATCH libnbd] api: Synchronous connect waits til all connections are connected.

> Should this be a bool parameter for the caller to opt-in to? In one > direction, returning as soon as possible allows the caller to issue > further synchronous commands which will pick the ready connections and > skip the ones still initializing, to at least get lower latency on the > first commands and better performance later as more connections come up; > in the other direction, waiting to return until all connections are made > makes it easier to issue async commands on any connection without > worrying if the connection is up. The choice of the parameter to pass in > depends, then, on whether the caller plans to make future sync calls or > async calls. It could be. On the other hand if people want to do complicated stuff then there is the AIO interface.

>> For ‘nbd_connect_command’, it essentially ignored multi-conn anyway, >> and I changed it so that it waits for conn[0] to get connected and >> returns, the other connections (if they exist) being ignored. It >> should probably be an error for the user to enable multi-conn on the >> handle and then use nbd_connect_command, but I did not make that >> change yet. > > Yes, that change (as a separate patch) makes sense. Even more radical, what if we prevent the use of multi-conn at all with the synchronous interface? (I don't think this is a good idea, just putting it out there for discussion).