Daylight Savings Time, Scheduler, and 100% CPU Usages


The following two entries in the scheduler have been causing Lucee (tomcat8.exe) to pin the server CPU at 100% since March 10, 2018.

The jobs ran at 2:45am on March 10, and then the server CPU instantly pinned at 100%. Even recycling Lucee and restarting the server had no impact. I changed the times to 3:45am and 3:50am, and everything went back to normal.

I assume the reason for this is that those times existed on March 10, so the jobs ran and the scheduler tried to schedule the next run for March 11 at 2:45am. However, that time does not exist because of daylight savings time. The 2am-3am hour is skipped on March 11, 2018.

I tried the two entries above on three different Lucee servers (all windows), and the same behavior happened on all of them. I would start Lucee, and try to load the Lucee administrator. Instantly, the CPU would pin at 100% and never recover.

Obviously, the easy workaround is to NOT schedule any daily jobs for 2-3am, but this is still a significant bug that drastically impacts server performance.


Windows 2012, Lucee, Scheduled Tasks


Zac Spitzer
October 10, 2020, 4:05 PM

With defined scheduled tasks maxes out the CPU (current time, not even set to DST switchover time )

Michael Offner
October 13, 2020, 6:31 AM

fixed regression in commit with version

Michael Offner
October 13, 2020, 6:32 AM

Michael Offner
October 13, 2020, 6:33 AM

please give this another try

Zac Spitzer
October 13, 2020, 8:23 AM

that fixed the CPU lockup bug I got with current time :)



Michael Offner


Michael Sprague




Fix versions

Affects versions