Port Queue

Each Port has its own Port queue.

The Port queue is maintained by the WMS, and specifies the sequence of Bins that AutoStore should plan for
each Port. The Port queue also specifies which Bins AutoStore selects on openbin requests.

Normally, the WMS will put prepared Bins in the Port queue, but this is not a requirement. The Port queue is
typically not very long. The WMS will normally defer this decision in order to avoid conflicts between Ports
(same bin required) and to consider preparation status.

The Bins in the Port queue are prioritized by their order (the sequence in which they are needed). Normally
the priority of the Bins in the Port queue is higher than the preparation queue, except for the backmost Bins of
a very long Port queue.

It is recommended to keep a Port queue that covers the next approximate 10-15 minutes of operation.

The Port queue may refer to content codes.

When an element in the Port queue refers to a content code, AutoStore will select a Bin with the specified
content code. AutoStore will never select a Bin that already exists in any Port queue or in the preparation
queue to replace a content code. When AutoStore selects a Bin on the openbin request where a content code
is the front element in the Port queue, then the selected bin_id replaces the content code as the front element
in the Port queue.

The front Bin leaves the Port queue when the Bin is closed in the Port. In Port mode AUTO, the front Bin
leaves the Port queue when the Bin is confirmed to Port.

Only the front bin is removed from the port queue. If another bin in the middle of the port queue is explicitly
selected by the WMS, it will not be removed from the port queue when it is closed.

Although a Bin normally leaves both the preparation queue and the Port queue simultaneously, these queues
are independent of each other.