Delay

MultiServer: Multiple servers in one object

The MultiServer object has the ability to delay one or more items at a time.

They can be classified as "Logical with Capacity and Process Delay".

MultiServers are used in situations where one or a number of items undergo a delay (representing some operation) in parallel or together.

Servers are objects that can hold items and apply a process delay time before releasing the items.

The process delay time can be zero, fixed, or made to vary from item to item, with a choice of distribution patterns.

Process delays are edited in Interaction View.

The number of items that may be held in the Multi-Server can be varied in the model over time.

This enables you to model situations such as workdays and weekends, lunch breaks, work shifts and regular down time.

MultiServer States

Idle No items are currently in the MultiServer.

Busy At least one item is currently in the MultiServer.

Blocked One or more items are blocked from leaving the MultiServer.

Unavailable The MultiServer has entered a period of zero server availability.

Note: A MultiServer with a capacity set to 0 sets itself to "Unavailable" state, as long as there are no items present or blocked in which case the busy/blocked states take priority.

Capacity

Enables the capacity of the MultiServer to be set.
The Capacity of a MultiServer may be determined in a range of ways:

As a constant value that does not change.

By reference to an Attribute which may change over time or change based on other conditions in the model during the model run.

Using an Attribute reference will enable the capacity to be changed during a model run.

For example, when an item enters the MultiServer the Attribute it is carrying can determine the new MultiServer capacity.

Server Limit

This setting enables Planimate® to allocate memory to accommodate the maximum number of servers you expect to be in the MultiServer during the run.

This sets a hard limit on how many items can undergo a delay at the MultiServer at the same time.

You then use the Capacity setting to vary the capacity dynamically over time, it you wish.

You need to ensure that the maximum Capacity you expect to provide is less than or equal to the Server Limit value.

If the Capacity value of the multi-server exceeds this Server Limit, the Server Limit is applied.

The maximum specifiable capacity limit of multiServers is 9999.

Show as Road Option

MultiServers may be configured to Act as a Road and animate items overtaking each other and moving at different speeds.

Pausable 0 Delay Option

Pauseable 0 Delay configures the multiServer to enable a pause of the model, even at zero time.

This enables a modeller to specify "pauseable points" in a long processing sequence which runs in zero time in a very controlled manner.

More details on Pauseable 0 Delay

No Blocking between Items Option

MultiServers have an option to prevent a blocked item from blocking other finished items.

This makes it act more like a dispatcher when many items are finished and one is blocked.

No blocking between items option is on by default for new servers.

If you turn this option off, you create a single exit point for a Multi-Server.

Whenever an item is blocked from leaving a multi-server, ALL subsequent items in the multiServer become blocked.

This single exit is sometimes useful because it maintains the exit order of the items, based on when they finished their delay.

Multi-server Interaction Editing

The delay an item undergoes is specific to its class and independent of any other activity in the Multi-Server.

The delay parameter needs to be set separately for each item class that will use it.

To set the delay time, shift to Interaction Edit View and click on the MultiServer.

A Distribution Pattern Dialog appears enabling the time to be set.

The time you set pertains only to the item class displayed in the Item Edit Box, whose paths you can see on the screen.

Refer to Editing Object Properties for information about editing properties common to all objects.