Dispose instances with KEEP_ALL_HISTORY_QOS

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Joined: 02/15/2013
Posts: 17
Dispose instances with KEEP_ALL_HISTORY_QOS

Hello,

how can I dispose an instance in the presence of KEEP_ALL_HISTORY_QOS? When I write to a keyed topic with KEEP_ALL multiple times on an instance and then start the reader I get all written data. Good so far. When I then call 'dispose' on that instance the reader sees all data and then a DDS_NOT_ALIVE_DISPOSED_INSTANCE_STATE. I assumed the writer would remove all data with the instance from the queue which it obviously does not. How can I 'clear' the writer queue if not with dispose()? Everything works as expected with KEEP_LAST_HISTORY_QOS, depth 1.

See following output:

Write to topic KEEP_LAST_HISTORY_QOS, 1:
  0002: Written 14.8 m/s
Reader:
  0002: Got 14.8 m/s

Dispose topic KEEP_LAST_HISTORY_QOS, 1:
  0002: Disposed sample
Reader:
  -No data-

Write to topic KEEP_ALL_HISTORY_QOS:
  0003: Written 17.1 m/s
  0003: Written 13.6 m/s
  0003: Written 18.0 m/s
  0003: Written 11.8 m/s
  0003: Written 8.6 m/s
Reader:
  0003: Got 17.1 m/s
  0003: Got 13.6 m/s
  0003: Got 18.0 m/s
  0003: Got 11.8 m/s
  0003: Got 8.6 m/s

Write topic KEEP_ALL_HISTORY_QOS:
  0003: Disposed sample
Reader:
  0003: Got 17.1 m/s
  0003: Got 13.6 m/s
  0003: Got 18.0 m/s
  0003: Got 11.8 m/s
  0003: Got 8.6 m/s
  0003: Dead 0.0 m/s

I could not find in the manual if this is a documented feature.

Thank you for your help.

Regards

Josef

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Last seen: 7 months 2 days ago
Joined: 02/15/2013
Posts: 17

Found the solution:

The following QoS in the XML file purges the DataWriter queue immediately

                <writer_data_lifecycle>
                    <autopurge_unregistered_instances_delay>
                        <sec>DURATION_ZERO_SEC</sec>
                        <nanosec>DURATION_ZERO_NSEC</nanosec>
                    </autopurge_unregistered_instances_delay>
                </writer_data_lifecycle>

The dispose() still stays in the queue (which might be helpful) but the unregister_instance() really removes the samples from the writer.

Regards

Josef