How can I fix Hyper.is (a third-party terminal program) when it freezes on idle too quickly for my needs?

Question

The terminal in question is: https://hyper.is MacOS 11.7.1 Big Sur is the operating system on a Macbook (2015). To troubleshoot this, I tried and reproduced the hang with Apple's native Terminal.app as well.

A remote connection with ssh stops responding after a short while (couple to 4 minutes) of inactivity on my computer. This doesn't happen while the power adapter is connected.

The .ssh/confing ServerAliveInterval doesn't help.

I tried to run in under screen and it still freezes.

One peculiar detail is that it keeps sending characters to remote host but doesn't show anything happening locally.

Here are screenshot from the Power options.

I can't find "Low power mode" anywhere.

It seems it's different for macbook laptops.

Answer 1

You didn’t indicate any error message like a “broken pipe” where the server is closing the connection due to inactivity and it always happens when disconnected from mains power and while idle (no activity) on your part. This is indicative of you Mac going into a power saving mode disconnecting the network connections.

Check your Battery settings

Check Low Power Mode; set it to “Never” to ensure your Mac doesn’t go into power saving mode when there’s no activity. You’ll also want to have your computer wake for network activity “Always” rather than the default if “on Power Adapter” (Battery → Options Button)

Modify your ssh config

Edit the ~/.ssh/config file (create if necessary) to set a low value interval:

Host foo.bar
ServerAliveInterval 120

This will send a “proof of life” signal every two minutes (120 seconds) to the server. You may want to tweak this if it still disconnects.

Keep the session alive on the server (preferred)

My preferred method is to use tmux or screen to keep whatever session you’re running on the server alive in the event of a disconnect. screen is usually included with macOS or Linux, but my preference is tmux. Either of these would be installed on the server and not the client.

I (personally) don’t recommend caffeinate or similar methods to override power saving algorithms. Instead, I will use tmux because it gives me a higher degree of safety in the event of a disconnect I have no control over like the Internet going down. tmux will keep my session alive on the server which is what matters most