Understanding job execution order

[FalcoSuessgott]

I would like to understand the exact order in which the jobs are being executed. Is it FIFO or is non deterministic? How is the execution order affected in singleton mode when a job is being rescheduled?

Thanks in advance

[JohnRoesler]

I would like to understand the exact order in which the jobs are being executed. Is it FIFO or is non deterministic?

The jobs are stored in a map. So, depending on how you add them to the scheduler, the answer is different.

1. If you add all your jobs to the map, and then start the scheduler, the range/iteration order for scheduling will be: https://go.dev/blog/maps#iteration-order

   the iteration order is not specified and is not guaranteed to be the same from one iteration to the next.

2. If you start the scheduler, and then add each job, they would be scheduled immediately, and so in the order that you add each job to the scheduler via NewJob

How is the execution order affected in singleton mode when a job is being rescheduled?
Singleton mode is scoped per job and this will only limit the job from running if the previously scheduled instance is still running. The order in which the job is executed depends on which job hits its schedule timer and fires off to the executor first.