Launching a dotnet process with real time causes all the runtime threads to have same priority

[deveshbahuguna]

Hi Folks,

We were migrating out WinCE based .net app to .NET 5 on linux. As WinCE was real-time OS the thread priorities used to have different behavior than regular windows or linux. Now when we launched our application with real time scheduling on then we had following observations:

1. .NET timer, Finalizer etc all having priority equal to Process .eg say process priority is 60 then all these thread have priority 60 which i think is wrong as maximum value a thread can have is 56 priority (Highest for 1-99 priority range)
2. Why are these dotnet-ust and timer threads spawned and what are their use?
3. What should be the priority of runtime GC,Timer,dotnet-ust etc threads?

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Issue Details

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Hi Folks,

We were migrating out WinCE based .net app to .NET 5 on linux. As WinCE was real-time OS the thread priorities used to have different behavior than regular windows or linux. Now when we launched our application with real time scheduling on then we had following observations:

1. .NET timer, Finalizer etc all having priority equal to Process .eg say process priority is 60 then all these thread have priority 60 which i think is wrong as maximum value a thread can have is 56 priority (Highest for 1-99 priority range)
2. Why are these dotnet-ust and timer threads spawned and what are their use?
3. What should be the priority of runtime GC,Timer,dotnet-ust etc threads?

Author:	deveshbahuguna
Assignees:	-
Labels:	area-System.Threading, untriaged
Milestone:	-

[mangod9]

Hi @deveshbahuguna, is this causing an issue for your scenario or are you asking why the thread priorities are not managed properly?

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