DDS_DurabilityServiceQosPolicy Struct Reference

Data Fields
struct DDS_Duration_t	service_cleanup_delay
	service cleanup delay
DDS_HistoryQosPolicyKind	history_kind
	history kind
int32_t	history_depth
	history depth
int32_t	max_samples
	maximum samples limit for the service
int32_t	max_instances
	maximum instances limit for the service
int32_t	max_samples_per_instance
	maximum samples per instance limit for the service

Detailed Description

The DurabilityServiceQosPolicy supports the durablity of data. The DDS API identifies several degrees of data durability.

1. VOLATILE: The data is volatile, and is not persisted beyond the initial publication.
2. TRANSIENT_LOCAL: The data is persisted locally within the source DataWriter. If that DataWriter is destroyed, or the containing application exits, the data is no longer available.
3. TRANSIENT: The data is persisted beyond the lifecycle of the originating DataWriter, and is available even after that DataWriter has been destroyed. However, data does not persist a reboot of the computer.
4. PERSISTENT: The data is persisted to 'off-line' storage, and is available even after a system reboot.

If a durability of TRANSIENT or PERSISTENT is specified, then a service beyond the source DataWriter must be established to provide advanced data durability. This QoS policy helps to configure that durablity service.

CoreDX DDS currently supports VOLATILE and TRANSIENT_LOCAL.