Fast disappearing space on boot drive

[ashleykaryl]

I tried converting my internal SATA hard drives to APFS like the SSD boot drive, which all appeared to go very smoothly. Not long after I looked down at the boot drive and saw there was suddenly about 30 gigs less available space and falling, though I can't say for sure if this is connected. It's now down to 64 gigs and I don't know what is going on here. Once or twice it's jumped up to around 72 gigs, then gone down again.

I tried booting into recovery mode, but for some reason that option no longer exists and it was never a problem with Sierra. Any idea what what could be causing this? I noticed that it seemed to go down faster when Time Machine was running, so I detached it from the computer.

Not long before I had a notification that High Sierra GM had been downloaded and was waiting to be installed, but I was doing something, so I didn't take any action and I wonder if that is related. Obviously I don't want to run out of space here.
[doublepost=1505516187][/doublepost]OK this is strange. I reattached Time Machine and let it run for a while. Then a minute ago the available space suddenly jumped back up to 94 gigs. I've never seen anything like this before and I'm assuming it's related to Time Machine. Could it be a conversion process between APFS and HFS+ that is taking up space?

 

[fxtlujd]

OK this is strange. I reattached Time Machine and let it run for a while. Then a minute ago the available space suddenly jumped back up to 94 gigs. I've never seen anything like this before and I'm assuming it's related to Time Machine. Could it be a conversion process between APFS and HFS+ that is taking up space?

I had the same issue. Looks like TimeMachine is not working with APFS correctly. When TimeMachine is enabled, space is not reclaimed when file is deleted, TimeMachnie snapshots keep growing. After disabling TimeMachine all the space is returned. I filled a bug with Apple. Please do the same to have it noticed.

 

[ashleykaryl]

Time machine has run various times since then without further problems, so it's possible this was a one time thing, but I will report it. I'm now on the GM version 17A362a of High Sierra. Curiously I gained a few more gigs after installing the GM version and now have a 100 gigs of space.

On a side note, I'm perplexed that external backup drives cannot also be formatted as APFS for Time machine.