Fraction of routees to be removed when the resizer reaches the backoffThreshold. For example, 0.1 would decrease 10% (rounded up), i.e. if current capacity is 9 it will request an decrease of 1 routee.

Minimum fraction of busy routees before backing off. For example, if this is 0.3, then we'll remove some routees only when less than 30% of routees are busy, i.e. if current capacity is 10 and 3 are busy then the capacity is unchanged, but if 2 or less are busy the capacity is decreased. Use 0.0 or negative to avoid removal of routees.

The fewest number of routees the router should ever have.

Number of messages between resize operation. Use 1 to resize before each message.

* Threshold to evaluate if routee is considered to be busy (under pressure). Implementation depends on this value (default is 1).

• 0: number of routees currently processing a message.
• 1: number of routees currently processing a message has some messages in mailbox.
• > 1: number of routees with at least the configured `pressureThreshold` messages in their mailbox. Note that estimating mailbox size of default UnboundedMailbox is O(N) operation.

Percentage to increase capacity whenever all routees are busy. For example, 0.2 would increase 20% (rounded up), i.e. if current capacity is 6 it will request an increase of 2 more routees.

The most number of routees the router should ever have. Must be greater than or equal to `lowerBound`.