Struct SchedState 

struct SchedState {
    buckets: Vec<BucketState>,
    demand: Vec<u64>,
    credits: Vec<u32>,
    parked: Vec<Option<Gate>>,
}

The scheduler’s mutable half.

Fields

buckets: Vec<BucketState>

One per ShapeProfile::buckets entry, in configured order.

demand: Vec<u64>

How many stream queues currently hold an unreleased head of this class. The demand a discipline arbitrates over.

Maintained by PendingQueue, which declares its head’s class and withdraws on every path that can retire one — including clear, the teardown drain and Drop. A leaked declaration would starve a lower class for the rest of the session, which is why the withdrawal is a Drop obligation and not a list of call sites.

credits: Vec<u32>

Releases remaining in this round, per class, under Discipline::WeightedRoundRobin. Refilled to ClassRule::weight when every class with demand in a bucket has spent its own.

parked: Vec<Option<Gate>>

The gate each starved class is parked on, or None when it is not parked. Taken and released by whoever makes the class eligible.