fastdds.xml

<?xml version="1.0" encoding="UTF-8" ?>
<profiles xmlns="http://www.eprosima.com/XMLSchemas/fastRTPS_Profiles">
    
    <transport_descriptors>

        <!-- We still want the default UDP transport to be present -->
        <transport_descriptor>
            <transport_id>udp_transport</transport_id>
            <type>UDPv4</type>
        </transport_descriptor>
    
        <!-- We want a customized version of the SHM transport -->
        <transport_descriptor>
            <transport_id>shm_transport</transport_id>
            <type>SHM</type>
            
            <!--
                Configure the size in bytes of the shared memory segment.
                On a Linux based system, you can get the maximum allowed value with
                    $ sysctl -a | grep shmmax
            -->
            <segment_size>5242880</segment_size>
            
            <!--
                The following value should be lower than or equal to segment_size.
                The default value is shown here.
            -->
            <maxMessageSize>5242880</maxMessageSize>
        </transport_descriptor>

    </transport_descriptors>

    <participant profile_name="CustomParticipant"  is_default_profile="true">
        <rtps>
            <!--
                As customized versions of the default transports are used, the
                built-in ones should be disabled
            -->
            <useBuiltinTransports>false</useBuiltinTransports>

            <!-- Link the Transport Layer to the Participant -->
            <userTransports>
                <transport_id>udp_transport</transport_id>

                <!-- Comment the following line in order to disable the SHM transport -->
                <transport_id>shm_transport</transport_id>
            </userTransports>
        </rtps>
    </participant>
</profiles>