MacBook Pro Sleeping During Backup

[Ric]

Last week I upgraded my 2015 MacBook Pro to macOS 10.13.4 and SuperDuper! to 3.1.4. I have a scheduled backup that occurs at 4:14 every morning -- the MacBook Pro is scheduled for wakeup at 4:14 and SuperDuper! is scheduled for 4:14. Ever since the upgrade, my MacBook Pro wakes up at the correct time and SuperDuper! launches, but the computer goes back to sleep before the backup starts. This morning, SuperDuper! had stopped on the countdown pop-up, but resumed backing up once I woke the computer. Some mornings it gets past the pop-up, but goes to sleep before the backup gets started and resumes when I wake the computer. Any thoughts on what might be causing this?

[dnanian]

We're doing two things to try to keep the Mac awake. First, as soon as our time-based schedule driver recognizes it's going to have to run copy (this should only take fractions of a second), we hold the Mac awake with "caffeinate":

/usr/bin/caffeinate -t 180 &> /dev/null &

That should keep the Mac awake for three minutes, which should be long enough to get going.

Second, when SuperDuper! starts a copy (basically, when it gets to the status window), we hold the Mac awake with a power assertion that says "don't go to sleep".

When you saw this happen, did we go to sleep before three minutes had elapsed?

[Ric]

I'm pretty sure the MacBook went back to sleep before three minutes was up. I'll check the system log when I get back home later today.

[dnanian]

Was the lid closed?

[Ric]

The lid was open.

[Ric]

One more thing to add -- I upgraded to macOS 10.13.4 last Thursday and Friday morning was the first time I noticed sleep interfering with SuperDuper!, which I had not upgraded to 3.1.4 yet (I did later that day). Something must have changed on the macOS side.