Scheduling

Scheduling

The patcherscheduler daemon wakes up every 10 minutes and checks whether any of the four patching phases are due. Most of the time it exits in milliseconds having done nothing; work only happens when a phase interval has elapsed.

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LaunchDaemon

The daemon is managed by:

/Library/LaunchDaemons/com.gilburns.patcher.scheduler.plist

It runs as root, which is required so Installomator can install applications system-wide.

Key plist settings:

Key	Value	Reason
StartInterval	600 (10 min)	Polling cadence — cheap when nothing is due
RunAtLoad	true	Runs once immediately on load (install, reboot)
SessionCreate	true	Required for launchctl asuser to display swiftDialog in the user's GUI session

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Phase Intervals

Each phase has its own interval preference:

Phase	Preference Key	Default
Scan	ScanIntervalDays	30 days
Check	CheckIntervalHours	4 hours
Stage	StageIntervalHours	4 hours
Apply	ApplyIntervalHours	24 hours

The scheduler records the last run time for each phase in Config/config.json and compares it against the current time on every wake.

Scan-on-Label-Update

When Installomator labels or Managed Labels are updated to a new version, the scan phase runs immediately regardless of the ScanIntervalDays interval. This ensures newly available labels are evaluated without waiting for the next scheduled scan.

Controlled by: ScanOnLabelUpdate (default: true)

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Monthly Patching Cadence

For environments that follow a monthly "Patch Tuesday" style schedule, set MonthlyPatchingCadenceEnabled to true. In this mode the apply phase is gated to a specific week and day of the month instead of running on the ApplyIntervalHours interval alone.

Relevant keys:

Key	Default	Description
MonthlyPatchingCadenceEnabled	false	Enable monthly mode
PatchingWeekday	3	Day of week (1=Sun … 7=Sat; 3=Tue)
PatchingWeekOfMonth	2	Which occurrence of that weekday (2 = second Tuesday)
PatchingStartTime	""	Optional HH:MM — don't start applying before this time
PatchingEndTime	""	Optional HH:MM — don't start applying after this time

In monthly mode the scheduler will not begin the apply phase until the configured patch day. Once the patch day arrives, ApplyIntervalHours still governs how often apply runs within that window.

Note: Deadline counters behave differently in monthly mode. In standard mode, daysPendingForDeadline counts from firstPendingDate. In monthly mode, it counts from the configured patch day of the current cycle. See Deferral and Deadlines.

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Startup Delay (Random Jitter)

To avoid all machines hammering external services simultaneously after a reboot, an optional random startup delay can be enabled:

Key	Default	Description
InitialScanDelayEnabled	false	Enable the startup delay
InitialScanDelayMaxSeconds	86400	Maximum jitter (default: up to 24 hours)

The scheduler picks a random number of seconds between 0 and InitialScanDelayMaxSeconds and waits that long before running the first scan after a cold start.

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Controlling the Daemon

# Check status
sudo launchctl print system/com.gilburns.patcher.scheduler

# Unload (stop)
sudo launchctl bootout system/com.gilburns.patcher.scheduler

# Load (start)
sudo launchctl bootstrap system /Library/LaunchDaemons/com.gilburns.patcher.scheduler.plist

# Trigger a run immediately
sudo launchctl kickstart system/com.gilburns.patcher.scheduler

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Log Files

The LaunchDaemon captures crash output to:

/Library/Logs/Patcher/scheduler_stdout.log
/Library/Logs/Patcher/scheduler_stderr.log

Detailed operational logs written by patcherscheduler itself go to:

/Library/Logs/Patcher/patcherscheduler.log

See Logs and Troubleshooting for more.