mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-21 15:39:58 +08:00
005dda25ff
From-SVN: r22461
24 lines
859 B
Plaintext
24 lines
859 B
Plaintext
This readme refers to the file thr-mach.c.
|
|
|
|
Under mach, thread priorities are kinda strange-- any given thread has
|
|
a MAXIMUM priority and a BASE priority. The BASE priority is the
|
|
current priority of the thread and the MAXIMUM is the maximum possible
|
|
priority the thread can assume. The developer can lower, but never
|
|
raise the maximum priority.
|
|
|
|
The gcc concept of thread priorities is that they run at one of three
|
|
levels; interactive, background, and low.
|
|
|
|
Under mach, this is translated to:
|
|
|
|
interactive -- set priority to maximum
|
|
background -- set priority to 2/3 of maximum
|
|
low -- set priority to 1/3 of maximum
|
|
|
|
This means that it is possible for a thread with the priority of
|
|
interactive to actually run at a lower priority than another thread
|
|
with a background, or even low, priority if the developer has modified
|
|
the maximum priority.
|
|
|
|
|