VRQ 0.97b is released with the following changes
1. Select a random rq when no preemptible rq available. This will help with removing the bottleneck when cpu number increased.
2. Add rr_interval kernel parameter. Now an "rr_interval=" kernel parameter is added, but it's not suggested to change the default rr_interval setting(6ms).
3. Introduce sched_prio_to_deadline[NICE_WIDTH] to simplify deadline calculation.
4. Extend NORMAL policy level to 7 levels, this change help with reducing rq look up cost when cpu number increased. And it also brings deadline fairness for different nice level NORMAL policy tasks. eg, when two nice 19 background tasks runs with 2 nice 0 front-ground tasks in a two cpus system, those two background tasks may both be on same cpu while normal tasks occupied another. In previous release, as a workaround for this use case, the background tasks need to be IDLE policy to trigger the policy fairness balance functionality. With this new changes, there is 7 NORMAL policy levels according to task's deadline, so the nice 19 background tasks(which likely have large virtual deadline) also can be triggered for the policy fairness balance functionality.
The main features for 0.97? release has been all set now for 4.13 kernel, these feature code has been running on my machines for 2week+, so they are consider stable. In next release, the major change will be renaming and documentation.
Enjoy VRQ 0.97a for
v4.13 kernel, :)
code are available at
All-in-one patch is available too.