Announcing a new version of MuQSS and a -ck release to go with it in concert with mainline releasing 4.8.5
MuQSS by itself for 4.8:
MuQSS by itself for 4.7:
This is a fairly substantial update to MuQSS which includes bugfixes for the previous version, performance enhancements, new features, and completed documentation. This will likely be the first publicly announced version on LKML.
EDIT: Announce here: LKML
- MuQSS is now a tickless scheduler. That means it can maintain its guaranteed low latency even in a build configured with a low Hz tick rate. To that end, it is now defaulting to 100Hz, and it is recommended to use this as the default choice for it leads to more throughput and power savings as well.
- Improved performance for single threaded workloads with CPU frequency scaling.
- Full NoHZ now supported. This disables ticks on busy CPUs instead of just idle ones. Unlike mainline, MuQSS can do this virtually all the time, regardless of how many tasks are currently running. However this option is for very specific use cases (compute servers running specific workloads) and not for regular desktops or servers.
- Numerous other configuration options that were previously disabled from mainline are now allowed again (though not recommended for regular users.)
- Completed documentation can now be found in Documentation/scheduler/sched-MuQSS.txt
- Fix for the various stalls some people were still experiencing, along with the softirq pending warnings.
- Fix for some loss of CPU for heavily sched_yielding tasks.
- Fix for the BFQ warning (-ck only)