Public Attributes | |
final Duration_t | max_data_availability_waiting_time |
Defines how much time to wait before delivering a sample to the application without having received some of the previous samples. | |
final Duration_t | max_endpoint_availability_waiting_time |
Defines how much time to wait to discover DataWriters providing samples for the same data source (virtual GUID). | |
final EndpointGroupSeq | required_matched_endpoint_groups |
A sequence of endpoint groups. |
Collaborative DataWriters
The Collaborative DataWriters feature allows having multiple DataWriters publishing samples from a common logical data source. The DataReaders will combine the samples coming from the DataWriters in order to reconstruct the correct order at the source.
This QoS policy allows you to configure the ordering and combination process in the DataReader and can be used to support two different use cases:
When com.rti.dds.infrastructure.PresentationQosPolicy.access_scope is set to PresentationQosPolicyAccessScopeKind.TOPIC_PRESENTATION_QOS or PresentationQosPolicyAccessScopeKind.INSTANCE_PRESENTATION_QOS, the virtual HB contains information about the samples contained in the com.rti.dds.publication.DataWriter history.
When com.rti.dds.infrastructure.PresentationQosPolicy.access_scope is set to PresentationQosPolicyAccessScopeKind.GROUP_PRESENTATION_QOS, the virtual HB contains information about all DataWriters in the com.rti.dds.publication.Publisher.
The frequency at which virtual HBs are sent is controlled by the protocol parameters com.rti.dds.infrastructure.RtpsReliableWriterProtocol_t.virtual_heartbeat_period and com.rti.dds.infrastructure.RtpsReliableWriterProtocol_t.samples_per_virtual_heartbeat.
Defines how much time to wait before delivering a sample to the application without having received some of the previous samples.
A sample identified by (GUIDn, SNm) will be delivered to the application if this timeout expires for the sample and the following two conditions are satisfied:
[range] [0, com.rti.dds.infrastructure.Duration_t.INFINITE], com.rti.dds.infrastructure.Duration_t.AUTO
Defines how much time to wait to discover DataWriters providing samples for the same data source (virtual GUID).
The set of endpoint groups that are required to provide samples for a data source can be configured using required_matched_endpoint_groups.
A non-consecutive sample identified by (GUIDn, SNm) cannot be delivered to the application unless DataWriters for all the endpoint groups in required_matched_endpoint_groups are discovered or this timeout expires.
[default] com.rti.dds.infrastructure.Duration_t.AUTO (com.rti.dds.infrastructure.Duration_t.INFINITE for PresentationQosPolicyAccessScopeKind.GROUP_PRESENTATION_QOS. Otherwise, 0 seconds)
[range] [0, com.rti.dds.infrastructure.Duration_t.INFINITE], com.rti.dds.infrastructure.Duration_t.AUTO
A sequence of endpoint groups.
In the context of Collaborative DataWriters, it specifies the set of endpoint groups that are expected to provide samples for the same data source.
The quorum count in a group represents the number of DataWriters that must be discovered for that group before the DataReader is allowed to provide non consecutive samples to the application.
A DataWriter becomes a member of an endpoint group by configuring the role_name in com.rti.dds.publication.DataWriterQos.publication_name.
[default] Empty sequence