Caution: On Windows, the value you choose for your process priority has a direct impact on how your
thread priorities are interpreted! You should never modify one without understanding what impact you are
doing so might have on the other!
5.82.2 Thread Priorities
On Linux/Unix hosts Hercules needs to be a setuid root program to allow it to reset its dispatching priority
to a high (negative) value (i.e. “chown root.root hercules; chmod +s hercules”).
For Windows the following conversions are used for translating Linux/Unix thread priorities to Windows
thread priorities:
Unix
Thread Priority
Windows
Thread Priority
Meaning
-20 to -16
Time Critical
Base priority of 15 for Idle, Below Normal, Normal, Above Normal,
or High class processes, and a base priority of 31 for Realtime
class processes.
-15 to -9
Highest
Priority 2 points above the priority class.
-8 to -1
Above Normal
Priority 1 point above the priority class.
0 to 7
Normal
Normal priority for the priority class.
8 to 15
Below Normal
Priority 1 point below the priority class.
16 to 19
Lowest
Priority 2 points below the priority class.
20
Idle
Base priority of 1 for Idle, Below Normal, Normal, Above Normal,
or High class processes, and a base priority of 16 for Realtime
class processes.
Table 9: Thread Priority Conversions
Caution: On Windows, your Thread Priority is interpreted differently based on your chosen Process Prio-
rity setting! You should never modify your Thread Priority settings without first reviewing your chosen Pro-
cess Priority setting!
