Option --maxThreads not working as expected

To debug out-of-memory errors with tapasco on Docker machines I was trying to run Tapasco with the --maxThreads option.

However the command tapasco --maxThreads 1 hls arraysum, arrayinit resulted in the following log:

$ tapasco --maxThreads 1 hls arraysum, arrayinit
[11:54:45 <main: Tapasco$> INFO] Running with configuration: [Configuration @/builds/tapasco/tapasco/default.cfg]
Verbose = None
KernelDir = /builds/tapasco/tapasco/kernel
CoreDir = /builds/tapasco/tapasco/core
ArchDir = /builds/tapasco/tapasco/arch
PlatformDir = /builds/tapasco/tapasco/platform
Slurm = false
Parallel = false
MaxThreads = 1
Jobs = List(HighLevelSynthesisJob(VivadoHLS,None,None,Some(ArrayBuffer(arraysum, arrayinit))))
[11:54:46 <pool-1-thread-1: VivadoHighLevelSynthesis$> INFO] starting run 'arrayinit' for axi4mm@pynq: output in /builds/tapasco/tapasco/core/arrayinit/axi4mm/pynq/hls/axi4mm.log
[11:54:46 <pool-1-thread-2: VivadoHighLevelSynthesis$> INFO] starting run 'arraysum' for axi4mm@pynq: output in /builds/tapasco/tapasco/core/arraysum/axi4mm/pynq/hls/axi4mm.log
[11:54:46 <pool-1-thread-3: VivadoHighLevelSynthesis$> INFO] starting run 'arrayinit' for axi4mm@vc709: output in /builds/tapasco/tapasco/core/arrayinit/axi4mm/vc709/hls/axi4mm.log
[11:54:46 <pool-1-thread-4: VivadoHighLevelSynthesis$> INFO] starting run 'arraysum' for axi4mm@vc709: output in /builds/tapasco/tapasco/core/arraysum/axi4mm/vc709/hls/axi4mm.log
[11:54:47 <pool-1-thread-5: VivadoHighLevelSynthesis$> INFO] starting run 'arrayinit' for axi4mm@zc706: output in /builds/tapasco/tapasco/core/arrayinit/axi4mm/zc706/hls/axi4mm.log
[11:54:47 <pool-1-thread-6: VivadoHighLevelSynthesis$> INFO] starting run 'arraysum' for axi4mm@zc706: output in /builds/tapasco/tapasco/core/arraysum/axi4mm/zc706/hls/axi4mm.log
[11:54:47 <pool-1-thread-7: VivadoHighLevelSynthesis$> INFO] starting run 'arrayinit' for axi4mm@zedboard: output in /builds/tapasco/tapasco/core/arrayinit/axi4mm/zedboard/hls/axi4mm.log
[11:54:47 <pool-1-thread-8: VivadoHighLevelSynthesis$> INFO] starting run 'arraysum' for axi4mm@zedboard: output in /builds/tapasco/tapasco/core/arraysum/axi4mm/zedboard/hls/axi4mm.log

From the description of --maxThreads I'd expect that Tapasco starts thread-2 after thread-1 has finished.