.NET Core Linux: Many child processes I didn't start

[dave-yotta]

I'm looking at one of our .NET core apps (console - hangfire job server app), running on linux on docker/kubernetes. I'm just a bit confused as to why we have so many child processes:

root@task-executor-85c5557b77-xnrdr:/# pstree 1 -a
sh /start-alloy-engine.sh -x task-executor
  `-dotnet AlloyTaskExecutor.dll
      `-76*[{dotnet}]

root@task-executor-85c5557b77-xnrdr:/# pstree 1 -a -p -g
sh,1,1 /start-alloy-engine.sh -x task-executor
  `-dotnet,535,1 AlloyTaskExecutor.dll
      |-{dotnet},536,1
      |-{dotnet},537,1
    ....

htop...
  PID USER      PRI  NI  VIRT   RES   SHR S CPU% MEM%   TIME+  Command
  535 root       20   0 8144M  220M 53612 S 143.  5.6 53:12.41 dotnet AlloyTaskExecutor.dll
  955 root       20   0 8144M  220M 53612 S 37.2  5.6  0:03.81 dotnet AlloyTaskExecutor.dll
  941 root       20   0 8144M  220M 53612 R 37.2  5.6  0:21.58 dotnet AlloyTaskExecutor.dll
  614 root       20   0 8144M  220M 53612 S 27.2  5.6 10:32.30 dotnet AlloyTaskExecutor.dll
  599 root       20   0 8144M  220M 53612 S 17.9  5.6  6:53.90 dotnet AlloyTaskExecutor.dll
  655 root       20   0 8144M  220M 53612 S 12.0  5.6  3:02.22 dotnet AlloyTaskExecutor.dll
  649 root       20   0 8144M  220M 53612 S  6.6  5.6  3:05.03 dotnet AlloyTaskExecutor.dll
  660 root       20   0 8144M  220M 53612 S  5.3  5.6  3:02.42 dotnet AlloyTaskExecutor.dll
  946 root       20   0 8144M  220M 53612 S  0.0  5.6  0:13.86 dotnet AlloyTaskExecutor.dll
  960 root       20   0 8144M  220M 53612 S  0.0  5.6  0:02.78 dotnet AlloyTaskExecutor.dll
  541 root       20   0 8144M  220M 53612 S  0.0  5.6  0:00.47 dotnet AlloyTaskExecutor.dll
    1 root       20   0  2388   408   296 S  0.0  0.0  0:00.11 /bin/sh /start-alloy-engine.sh -x task-executor
  536 root       20   0 8144M  220M 53612 S  0.0  5.6  0:00.00 dotnet AlloyTaskExecutor.dll
  537 root       20   0 8144M  220M 53612 S  0.0  5.6  0:00.00 dotnet AlloyTaskExecutor.dll
....

There are a lot of dotnet AlloyTaskExecutor.dll processes that are all children of the one I created. This is happening on all our apps when run on linux, not seeing it on windows.

I'm looking into resource usage of this app here, so it's a bit confusing.

Is this some kind of way multitasking is done on .net core linux?

I may want to do some profiling - which process do I even attach to? Just PID 535?

Is it something we've done?

We have no Process.Start in our codebase, so it may be a 3rd party lib doing this.

They are all trying to run our app with default args? Is there a different way to change the entrypoint I'm not seeing here?

Any advice to find the culprit? I've thought of changing the process security to deny process spawning but I don't know how to do this on linux.

ps aux and top are only showing one process, not sure why that is either.

Are these forked processes maybe? If it helps the app is running hangfire with a redis storage provider.

[PathogenDavid]

These are just individual threads within the same process. In htop if you press F2 you can hide them, color them differently, and show their custom thread names. (IE: Thread.Name)

For example, here's what it looks like if you enable coloring them differently and showing thread names:

The reason things look the way they do by default is the line between a thread and a process is slightly blurrier on Linux. (This elaborates a bit more)