Got my base M1 mini with 8GB of RAM and 256GB SSD on February 13th. With just simple content consumption (browser, Spotify, messaging) as of now it has written over 20TB of data! That is insane.
I had to switch off Time Machine on MacbookHD (main disk) by excluding it from the Time Machine preferences, and reinstall the OS to erase the previous copies it had made, all ~400GB of it (on my 499GB disk)... As the user, I was not asked for permission to allow Time Machine to use up to 80% of available disk capacity. It was backing up so many copies of the data until I noticed I had left only 8GB of free space and I only noticed because Quicktime screen recording started crashing due to insufficient disk space. Basically, the decision by Apple is to use up to 80% of the available disk space to save copies of the data on that disk without user permission, and because it checks and reconciles the amount it's using every so often you can easily end up with 0% free capacity if you e.g. record a lot of videos in between.
I am not quite sure if this Time Machine business is directly related (though it might be due by poorly optimized rewrites, particularly if there’s outstanding hardware shenanigans with encryption on M1s). It is baffling that the disk usage appears to be a deliberate decision.
Only after publication on news sites they fixed it.
Won't be surprised if the bug regressed and happened again.
I don't use Spotify (not available in my country), so I wouldn't know, but I bet half of the reports are because of some badly written third party app constantly writing in 4kb chunks with O_DIRECT or fsync() all the time.
Also worth noting that I see my swap fluctuating from 6-8GB almost all the time (granted I have multiple browser tabs and windows, maybe like 10-30 ish ?)
From the activity monitor: Uptime 1 day & 6 hours Kernel_task : 418 GB written - 84 GB read Microsoft edge helper: 23-4 Launchd: 19-1 Mds_stores: 9-9 Photolibraryd: 4-8
In the last 24 hours I have not touched the mini, I just switched it on yesterday to check something online and switched off the monitor.