Finding out what's commanding motor move?

["J. Lewis Muir via Tech-talk" <tech-talk@aps.anl.gov>]

Hi!

I've got an EPICS motor that appears to be being commanded to move in
increments of 0.001 mm every ~0.9 s, sometimes pausing maybe once a
minute for 3-5 s and then continuing, and I can't figure out where this
is coming from.  Nothing should be commanding the motor to move.  Below
is a short camonitor output showing this.  Has anyone seen this before,
or does anyone know how I could track this down?

The environment is the following:

* Architecture: x86_64
* EPICS 7.0.8.1
* motor 7.3.1
* motorAcsMotion 2.2 (+ commits up to c2d67e7, + patches for 719d3ca and
  f4442ee)
* Motor controller: ACS SPiiPlusEC

I could restart the IOC or the motor controller and see if the problem
goes away, but I'm also very puzzled by this and not wanting to lose my
chance to figure out what is happening.

I wondered if maybe an MEDM client could have gone wrong, or maybe at
some point a user had clicked the MEDM motor tweak button rapidly or who
knows what, and something has queued up move requests, or an MEDM client
has a bug and is sending requests.  I tried killing MEDM clients, but
the behavior remains.  (It's possible, though, that I didn't kill all of
the MEDM clients.)  And of course, this could have nothing to do with
MEDM at all.

----
$ camonitor 17idb:m49.{VAL,RBV}
17idb:m49.VAL                  2025-10-10 09:49:09.164067 0.3198
17idb:m49.RBV                  2025-10-10 09:49:09.164067 0.319806
17idb:m49.VAL                  2025-10-10 09:49:09.811336 0.3208
17idb:m49.RBV                  2025-10-10 09:49:09.942664 0.320808
17idb:m49.RBV                  2025-10-10 09:49:10.048250 0.320799
17idb:m49.VAL                  2025-10-10 09:49:10.694218 0.3218
17idb:m49.RBV                  2025-10-10 09:49:10.823829 0.321805
17idb:m49.RBV                  2025-10-10 09:49:10.929981 0.321801
17idb:m49.VAL                  2025-10-10 09:49:11.575012 0.3228
17idb:m49.RBV                  2025-10-10 09:49:11.710083 0.322803
17idb:m49.RBV                  2025-10-10 09:49:11.816005 0.322795
17idb:m49.VAL                  2025-10-10 09:49:12.463081 0.3238
17idb:m49.RBV                  2025-10-10 09:49:12.488690 0.322803
17idb:m49.RBV                  2025-10-10 09:49:12.594706 0.323805
17idb:m49.VAL                  2025-10-10 09:49:13.346730 0.3248
17idb:m49.RBV                  2025-10-10 09:49:13.372604 0.323801
17idb:m49.RBV                  2025-10-10 09:49:13.478568 0.324807
17idb:m49.RBV                  2025-10-10 09:49:13.584573 0.324803
17idb:m49.VAL                  2025-10-10 09:49:14.229819 0.3258
17idb:m49.RBV                  2025-10-10 09:49:14.254400 0.324794
17idb:m49.RBV                  2025-10-10 09:49:14.360413 0.325805
17idb:m49.VAL                  2025-10-10 09:49:15.112347 0.3268
17idb:m49.RBV                  2025-10-10 09:49:15.138748 0.3258
17idb:m49.RBV                  2025-10-10 09:49:15.244889 0.326806
17idb:m49.RBV                  2025-10-10 09:49:15.351075 0.326794
----

Thank you!

Lewis