2.3. StatusData

The eProsima Fast DDS Statistics Backend records entities status data of different nature, as provided by the Monitor Service from eProsima Fast DDS Statistics Module, e.g., incompatible QoS or the number of lost samples. We refer to the nature of these status data values as their StatusKind.

• PROXY: Collection of parameters describing the proxy data of that entity.

• CONNECTION_LIST: List of connections used by this entity. Each of the elements is a connection where the possible values for the connection mode are:

  • Intraprocess

  • Data sharing

  • Transport

  In addition, information comprising the announced locators and locator in use with each one of the matched entities is also included.

• INCOMPATIBLE_QOS: Status of the incompatible QoS of that entity.

  • DATAWRITER Incompatible QoS Offered.

  • DATAREADER Incompatible QoS Requested.

• LIVELINESS_LOST: Tracks the status of the number of times that liveliness was lost by a DATAWRITER.

• LIVELINESS_CHANGED: Tracks the status of the number of times that liveliness status changed in a DATAREADER.

• DEADLINE_MISSED: The status of the number of missed deadlines registered in that entity.

• SAMPLE_LOST: Tracks the number of times that this entity lost samples.

Only PARTICIPANT, DATAWRITER and DATAREADER have associated status data. The following table describes which StatusKind each of these entities has:

StatusKind	PARTICIPANT	DATAWRITER	DATAREADER
PROXY	Yes	Yes	Yes
CONNECTION_LIST	Yes	Yes	Yes
INCOMPATIBLE_QOS	No	Yes	Yes
LIVELINESS_LOST	No	Yes	No
LIVELINESS_CHANGED	No	No	Yes
DEADLINE_MISSED	No	Yes	Yes
SAMPLE_LOST	No	No	Yes

Each StatusKind has an associated StatusLevel. OK status is obtained when the monitor service message reports no problem. Entity’s associated StatusLevel is obtained from all status data. The following table describes which StatusLevel’s are associated with each StatusKind:

StatusKind	StatusLevel’s
PROXY	OK
CONNECTION_LIST	OK
INCOMPATIBLE_QOS	OK/ERROR
LIVELINESS_LOST	OK/WARNING
LIVELINESS_CHANGED	OK
DEADLINE_MISSED	OK/WARNING
SAMPLE_LOST	OK/WARNING

Note

For entity transitions, WARNING status level takes precedence over OK level, and ERROR does over WARNING and OK levels.