Presenter screen lags, can take a long time for updates

[tsmith512]

This was reported by the stage manager as intermittent, but I saw it in rehearsal last night. Sometimes the presenter screen on the projector will "wake up" and show the cue within 5-10 seconds of being activated, but occasionally it never updated. My phone, the stage manager's laptop, and my own laptop on the debug screen all updated near instantly.

[tsmith512]

Preliminary research: The laptop attached to the projector was running Safari. Apparently Safari is more aggressive with throttling unfocused windows or when the user is idle. Since a lot of Socket.io's internals seem to be driven on setInterval and setTimeout events to fire polling for updates, that's my leading theory. Testing with my laptop running Chrome on the presenter and firing events from my phone on the SM display every 15-30 minutes, there was never any lag, on the same network.

[tsmith512]

The "work" to address this issue so far is "don't use Safari on the computer attached to the projector." See socketio/socket.io#2924 which appears related --- but since the show is this week, I don't think I'm gonna get a workaround in.

[tsmith512]

No updates here, it was fine in rehearsal and postshow testing last night. Closing -- not "resolved" but "works for this scenario"