Realtime thread priorities

David Xu davidxu at
Fri Dec 17 14:06:43 UTC 2010

John Baldwin wrote:
> Yes, we do not do priority lending for sleep locks, and to date we never
> have.  This is not a new problem and moving RT priority higher is not
> introducing any _new_ problems.  However, it does bring _new_ functionality
> that some people need.  Just because you don't need it doesn't mean it isn't
> important.
> Don't let the perfect be the enemy of the good.
I guess that your real requirement is preempting at user boundary
for static priority thread, however current code does not. I doubt that
preempting in kernel path which holding an unknown lock has any
visible benefit for your application. Yes, perfect is not the enemy but
the goal, isn't mutex with priority propagating for perfect ?

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