ramp.up.period.in.seconds=0 does not work

I guess the log says it all. The last part repeats for inifinity. Nothing gets executed.
With ramp.up.period.in.seconds=1 and a large number users he gets quickly hickups till he chokes kompletely thill he is also sending nearly nothing out. We use a custom HTTP conection, bit this should not matter i guess?

2020-07-29 10:55:38,405 [main] WARN org.jsmart.zerocode.parallel.ExecutorServiceRunner -
LOAD:
-----------------------------------
### numberOfThreads : 6
### rampUpPeriodInSeconds : 0
### loopCount : 2500000
-----------------------------------

2020-07-29 10:55:38,421 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,421 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.421227500
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [pool-2-thread-1] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-1 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [pool-2-thread-2] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-2 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [pool-2-thread-3] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-3 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [pool-2-thread-4] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-4 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [pool-2-thread-5] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-5 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [pool-2-thread-6] INFO org.jsmart.zerocode.core.runner.parallel.LoadProcessor - pool-2-thread-6 Parallel Junit test- *Start. Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,436 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.436891800
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Start... Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - main Executor - *Finished Time = 2020-07-29T10:55:38.452522300
2020-07-29 10:55:38,452 [main] INFO org.jsmart.zerocode.parallel.ExecutorServiceRunner - Waiting for the next test flight to adjust the overall ramp up time, waiting time in the transit now = 0.0