Mac - Period Pause/freezing like clockwork

[PaulTech]

Issue: Mac mini "Core i7" 3.2 (Late 2018) upgraded to Mac OS X (10.15.7) because of seemingly random freezes when clients running Filemaker 18 accessed the Filemaker Server on this machine. Time Machine was suspected so it was set to manual as other backups are in place including Carbon Copy Cloner that runs every few weeks. "NAP" is turned off. The client reported that all connected Filemaker Clients experienced freezing on one day at: "8:41am, 9:41am, 10:41am, 11:41am, 12:41pm, 1:41pm, 2:41pm, 3:41pm, 4:41pm, and again at 5:41pm."

What I suspect is there is a Cron/Launchd that is running at this time, however, I'm not sure how to find the culprit lacking experience in this area if someone has an app or some instructions to follow?

Or, maybe there's another reason for this issue?

I did look at the logs in Console and there were 2 "Spin" entries at the X:41 minute marks. Could not discern the reason other than the service was listed as logd but I'm assuming that just how the log was generated.

 

[timeshifter]

What I suspect is there is a Cron/Launchd that is running at this time, however, I'm not sure how to find the culprit lacking experience in this area if someone has an app or some instructions to follow?

Does this help?

How to List All Cron Jobs on a Mac or Linux PC

Need to quickly see a list of all cron jobs on a computer? You can easily see all scheduled cron jobs by using the crontab command, and seeing cron data works the same on Mac as well as Linux and m…

osxdaily.com

 

[overburnz]

I know that some Mac mini 2018 have had some issues with USB devices connected to the unit, does he have any external HD's ou anything else connected?

 

[Markverhyden]

I'd be checking what the client machines are logging as well.

 

[PaulTech]

I know that some Mac mini 2018 have had some issues with USB devices connected to the unit, does he have any external HD's ou anything else connected?

Burning Bytes - thanks for the heads up. Ejected the external, no luck. Still stalling at the 41 minute mark every hour.

 

[overburnz]

Burning Bytes - thanks for the heads up. Ejected the external, no luck. Still stalling at the 41 minute mark every hour.

if it's still in warranty I would advise you to redirect the customer to an AASP

 

[PaulTech]

It looks like it was due to spotlight and indexing. Since disabling the mdutil service no more freezes. The plan is to leave it off until next week to confirm and then add exclusion locations for the Filemaker data location followed by a reindex overnight. Here is the process for reference:

Start and stop indexing via terminal:
sudo mdutil -a -i off
sudo mdutil -a -i on

Exclude locations with lots of file changes: System Preferences > Spotlight > Privacy tab > drag-and-drop onto it any directories not to index.

To start the re-index, recommended in the evening or a slow period:

sudo mdutil -E / <- causes spotlight to reindex
or
sudo rm -rf /.Spotlight-V100/* <- erases spotlight database and causes it to reindex

 

[PaulTech]

Just curious, any longterm side effects to turning off mdutil? This is a host server machine so no one is using it as a daily work machine.

 

[Markverhyden]

mdutil is just for indexing. So, in theory, if indexing is off that just means it'll take longer to find things that aren't indexed. But if it's only for FMP it shouldn't really matter.

I had a customer who was having indexing issues with Outlook which is indexed with mdutil. Spent hours trying all kinds of stuff. In the end I had to create a new use and move everything over. I did run it with mdutil disabled and, excepting for search problems, never had any other issues.