What is spinning my disks?

Time Machine?

What spins y’ discs, is whatever turns you on. :smiling_imp: As well as Time Machine, obviously.

Take care

If it started recently, there was a bug in 10.14 a few iterations back that would needlessly spin up external drives. It should be fixed by now, so make sure you’re patched up.

Otherwise, try the fs_usage CLI tool. In its raw state it will be too noisy to be useful, so what you’ll probably want to do is grep the output by the volume name—and if it is a Time Machine volume, you should be able to filter out that activity using an inverse search. If you aren’t using the drive yourself for anything you could leave it running for a while.

It could be any number of things! I just gave it a whirl on my system, and my third-party file manager (ForkLift) periodicially accesses it (getattrlist mainly), git does, my peer to peer syncing tool (which doesn’t actually sync anything on that disk, but it seems to use lstat and statfs periodically. Those seem to be the main culprits. System level stuff: iconservices pings every once in a while—again for getattrlist. LaunchBar also checks in now and then. I note most of these requests are aimed at my at cloned (not TM) full system backup folder which includes an /Applications folder. So it seems some of these tools are considering that to be a blessed Applications folder—which is weird to me. Although LaunchBar trawls it, I don’t get hits when trying to launch software that only exists in that backup folder.

Whether these are active or reactive requests, I don’t know, but it does seem to be that the more tools you have running that work at the file system level, the more likely the drive will “tick” now and then.

you likely have an open program looking to see “have files changed”. I found a finder window minimized that was doing that to me (was set to open at startup the crafty batard (because family forum)). I’ve noticed that pages, EVEN WHEN CLOSED will do that if I last saved to an external drive (but I have not removed it).

This may be part of the bug IOA mentioned,

My solution to the above is to reinstate my normal level of mistrust of all internal saves.

  1. save to temp folder on boot disk
  2. quit software
  3. manually move file to destination
  4. compare files
  5. delete save.

I don’t do that with scriv because it never does stupid things like this. :slight_smile:

A useful tool (free to use)––Consolation 3––created by Howard Oakley to access Apple’s unified log can be found at his site:

Consolation overview:
eclecticlight.co/2019/05/20/bro … e-at-last/

A search at the site for Consolation will find more info, including mock investigations of a crash and of Time Machine errors.

AmberV & Jaysen are probably right, but it could be disk gnomes dancing. Just keep on their good side & you should be fine…