computing

type Controller struct {
	// contains filtered or unexported fields
}

type DeviceBackend interface {
	ReadTokenState(device int) (*TokenState, error)
	WriteTokenState(device int, state *TokenState) error
	ReadQuota(device int) (*DeviceQuota, error)
	WriteRefillRate(device int, refillRate float64) error
	WriteCapacity(device int, capacity float64) error
	FetchSubTokens(device int, cost float64) (float64, error)
	FetchAddTokens(device int, amount float64) (float64, error)
}

type DeviceController struct {
	// contains filtered or unexported fields
}

type DeviceControllerConfig struct {
	// Target GPU utilization (0.0 to 1.0, e.g., 0.5 = 50%)
	TargetUtilization float64

	// Minimum refill rate (tokens/second) - prevents rate from dropping to zero
	RateMin float64

	// Maximum refill rate (tokens/second)
	RateMax float64

	// PID proportional gain - how aggressively to respond to error
	Kp float64

	// PID integral gain - how quickly to eliminate steady-state error
	Ki float64

	// PID derivative gain - how much to dampen oscillations
	Kd float64

	// Low-pass filter coefficient for smoothing utilization (0.0 to 1.0)
	// Higher values = less filtering (more responsive, more noise)
	FilterAlpha float64

	// Burst window in seconds - capacity = refill_rate × burst_window
	BurstWindow float64

	// Minimum capacity (tokens)
	CapacityMin float64

	// Maximum capacity (tokens) - prevents unbounded growth
	CapacityMax float64

	// Minimum time between updates (seconds)
	MinDeltaTime float64

	// Integral decay factor (0.0 to 1.0) for exponential decay of integral term
	// Higher values (closer to 1.0) = slower decay, retains more history
	// Lower values = faster decay, responds more quickly to changes
	// Default 0.95 means ~20 update cycles for integral to decay to ~35.8% of original value
	IntegralDecayFactor float64
}

type DeviceControllerState struct {
	TargetUtilization   float64
	SmoothedUtilization float64
	CurrentRate         float64
	CurrentCapacity     float64
	TokenDrainRate      float64
}

type DeviceQuota struct {
	Capacity   float64
	RefillRate float64
}

type TokenState struct {
	Tokens     float64
	LastUpdate float64
}