DURABILITY
[QoS Policies]

This QoS policy specifies whether or not RTI Data Distribution Service will store and deliver previously published data samples to new DDSDataReader entities that join the network later. More...

Classes

struct  DDS_DurabilityQosPolicy
 This QoS policy specifies whether or not RTI Data Distribution Service will store and deliver previously published data samples to new DDSDataReader entities that join the network later. More...

Enumerations

enum  DDS_DurabilityQosPolicyKind {
  DDS_VOLATILE_DURABILITY_QOS,
  DDS_TRANSIENT_LOCAL_DURABILITY_QOS,
  DDS_TRANSIENT_DURABILITY_QOS,
  DDS_PERSISTENT_DURABILITY_QOS
}
 Kinds of durability. More...

Variables

const char *const DDS_DURABILITY_QOS_POLICY_NAME
 Stringified human-readable name for DDS_DurabilityQosPolicy.

Detailed Description

This QoS policy specifies whether or not RTI Data Distribution Service will store and deliver previously published data samples to new DDSDataReader entities that join the network later.


Enumeration Type Documentation

Kinds of durability.

QoS:
DDS_DurabilityQosPolicy
Enumerator:
DDS_VOLATILE_DURABILITY_QOS  [default] RTI Data Distribution Service does not need to keep any samples of data instances on behalf of any DDSDataReader that is unknown by the DDSDataWriter at the time the instance is written.

In other words, RTI Data Distribution Service will only attempt to provide the data to existing subscribers.

DDS_TRANSIENT_LOCAL_DURABILITY_QOS  RTI Data Distribution Service will attempt to keep some samples so that they can be delivered to any potential late-joining DDSDataReader.

Which particular samples are kept depends on other QoS such as DDS_HistoryQosPolicy and DDS_ResourceLimitsQosPolicy. RTI Data Distribution Service is only required to keep the data in memory of the DDSDataWriter that wrote the data.

Data is not required to survive the DDSDataWriter.

For this setting to be effective, you must also set the DDS_ReliabilityQosPolicy::kind to DDS_RELIABLE_RELIABILITY_QOS.

DDS_TRANSIENT_DURABILITY_QOS  RTI Data Distribution Service will attempt to keep some samples so that they can be delivered to any potential late-joining DDSDataReader.

Which particular samples are kept depends on other QoS such as DDS_HistoryQosPolicy and DDS_ResourceLimitsQosPolicy. RTI Data Distribution Service is only required to keep the data in memory and not in permanent storage.

Data is not tied to the lifecycle of the DDSDataWriter.

Data will survive the DDSDataWriter.

DDS_PERSISTENT_DURABILITY_QOS  Data is kept on permanent storage, so that they can outlive a system session.


Variable Documentation

const char* const DDS_DURABILITY_QOS_POLICY_NAME

Stringified human-readable name for DDS_DurabilityQosPolicy.


RTI Data Distribution Service C++ API Version 4.5e Copyright © 23 Oct 2011 Real-Time Innovations, Inc