Changing PRESENTATION QoS for RTI Perftest

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Changing PRESENTATION QoS for RTI Perftest

Hello,

Currently, I am running RTI Perftest to learn more about the effect of QoS policies on throughput and latency. I am interested to change the PRESENTATION QoS policy in the perftest_qos_profiles.xml file. 

<publisher_qos>
   <presentation>
      <access_scope>TOPIC_PRESENTATION_QOS</access_scope>
      <ordered_access>true</ordered_access>
   </presentation>
</publisher_qos>

The above setting is the default PRESENTATION QoS setting. I would like to change it to coherent_access so would changing the ordered_access to "false" would work? 

 

Thanks in advance. 

 

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Joined: 08/28/2013
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you will need to add <coherent_access>true</coherent_access>, then that will cause some errors, since, as you can read in the documentation:

  • DDS_BOOLEAN_TRUE:Changes made to instances within each DataWriter will be available to the DataReader as a coherent set, based on the value of access_scope. Not supported for access_scope = GROUP.

That will imply that you will need to change the access_scope as well, and then the ordered_access, as you can see here in the doc as well:

  • DDS_BOOLEAN_FALSE:The order of DDS samples is only preserved for each instance, not across instances. The value of access_scope is ignored.

  • DDS_BOOLEAN_TRUE:The order of DDS samples from a DataWriter is preserved, based on the value set in access_scope.

This might help: https://community.rti.com/static/documentation/connext-dds/6.0.1/doc/manuals/connext_dds/html_files/RTI_ConnextDDS_CoreLibraries_UsersManual/Content/UsersManual/PRESENTATION_QosPolicy.htm