Scott Rotondo wrote:
> Garrett D'Amore wrote:
>> As far as this case goes, I'd better like to understand why we needed
>> a new class, instead of just using SYS.
>
> That's the key question, which I haven't really seen anyone address in
> this PSARC email thread. However, you can find a high-level answer in
> CR 6806882:
>
> "The basic issue is that the SYS scheduling class was not designed for
> long-running CPU intensive workloads. We introduce a new SDC (System
> Duty Cycle) scheduling class, which adjusts its threads' priority in
> order to give them a specified percentage of the processor.
> It also gives them a scheduling quantum, which gives other threads at
> the same priority on the same CPU a chance to run."
>
> Scott
>
So my read of the above is that this is an attempt to give userland-like
scheduling properties to kernel threads (perhaps somewhat like the FX
class?). Which further underscores the fact that making this class
available to user threads is probably pointless.
- Garrett
