I upgraded a early 2013 MBP Retina to 10.13.2, and obtained a new external 4TB drive to do TM backups to.
Time Machine now pukes after a semi-random period of time -- 20 to 60 minutes. Here's what the console says
default 17:52:06.139471 -0600 powerd Process backupd.8811 ClientDied PreventUserIdleSystemSleep "Time Machine backup" age:00:18:24 id:4295008645 [System: PrevIdle DeclUser IntPrevDisp kDisp]
default 17:52:06.140737 -0600 powerd Process backupd.8811 ClientDied BackgroundTask "Time Machine backup" age:00:18:24 id:47244681604 [System: PrevIdle DeclUser IntPrevDisp kDisp]
What's more, the icon in the menu bar no longer spins.
What in the world is going on?