TibrvCmQueueTransport()

Constructor

Declaration

TibrvCmQueueTransport(
    TibrvRvdTransport    transport,
    java.lang.String     cmName)
  throws TibrvException
TibrvCmQueueTransport(
   TibrvRvdTransport    transport,
   java.lang.String     cmName,
   int          workerWeight,
   int          workerTasks,
   int          schedulerWeight,
   double       schedulerHeartbeat,
   double       schedulerActivation)
 throws TibrvException

Purpose

Create a transport as a distributed queue member.

Remarks

The new TibrvCmQueueTransport must employ a valid TibrvRvdTransport for network communications.

Parameter

Description

transport

The new TibrvCmQueueTransport employs this TibrvRvdTransport object for network communications.

Destroying the TibrvCmQueueTransport does not affect this transport.

cmName

Bind this reusable name to the new transport object, which becomes a member of the distributed queue with this name.

The name must be non-null, and conform to the syntax rules for Rendezvous subject names. It cannot begin with reserved tokens. It cannot be a non-reusable name generated by a call to TibrvCmTransport(). It cannot be the empty string.

For more information, see Reusable Names on page 140 in TIBCO Rendezvous Concepts.

workerWeight

When the scheduler receives a task, it assigns the task to the available worker with the greatest worker weight.

A worker is considered available unless either of these conditions are true:

The pending tasks assigned to the worker member exceed its task capacity.
The worker is also the scheduler. (The scheduler assigns tasks to its own worker role only when no other workers are available.)

When omitted, the default value is 1.

workerTasks

Task capacity is the maximum number of tasks that a worker can accept. When the number of accepted tasks reaches this maximum, the worker cannot accept additional tasks until it completes one or more of them.

When the scheduler receives a task, it assigns the task to the worker with the greatest worker weight—unless the pending tasks assigned to that worker exceed its task capacity. When the preferred worker has too many tasks, the scheduler assigns the new inbound task to the worker with the next greatest worker weight.

The value must be a non-negative integer. When omitted, the default value is 1.

Zero is a special value, indicating that this distributed queue member is a dedicated scheduler (that is, it never accepts tasks).

Warning 

Tuning task capacity to compensate for communication time lag is more complicated than it might seem. Before setting this value to anything other than 1, see Task Capacity on page 160 in TIBCO Rendezvous Concepts.

schedulerWeight

Weight represents the ability of this member to fulfill the role of scheduler, relative to other members with the same name. Cooperating members use relative scheduler weight values to elect one member as the scheduler; members with higher scheduler weight take precedence.

When omitted, the default value is 1.

Acceptable values range from 0 to 65535. Zero is a special value, indicating that the member can never be the scheduler. For more information, see Rank and Weight on page 178 in TIBCO Rendezvous Concepts.

schedulerHeartbeat

The scheduler sends heartbeat messages at this interval (in seconds).

All TibrvCmQueueTransport objects with the same name must specify the same value for this parameter. The value must be strictly positive. To determine the correct value, see Step 4: Choose the Intervals on page 207 in TIBCO Rendezvous Concepts.

When omitted, the default value is 1.0.

schedulerActivation

When the heartbeat signal from the scheduler has been silent for this interval (in seconds), the cooperating member with the greatest scheduler weight takes its place as the new scheduler.

All TibrvCmQueueTransport objects with the same name must specify the same value for this parameter. The value must be strictly positive. To determine the correct value, see Step 4: Choose the Intervals on page 207 in TIBCO Rendezvous Concepts.

When omitted, the default value is 3.5.

See Also

TibrvCmQueueTransport.destroy()

Distributed Queue, page 155, in TIBCO Rendezvous Concepts