1.3.2. Discovery Performance¶

Work In Progress

Endpoint Discovery

The following graph displays the time it takes to complete endpoint discovery, per number of participants. There is one endpoint for each participant; across all participants, half the endpoints are DataWriters and half are DataReaders. For each scenario, we graph three values: the maximum, median, and minimum times that the participants took to complete endpoint discovery. (Maximums and minimums are the dashed lines; medians are the solid lines).

The parameters for testing this scenario are:

Number of hosts: 12

Participants in the system: <variable we increase>

Topics in the system: 1

Readers per topic: half of the participants

Writers per topic: half of the participants

QoS profiles used: DynamicProfile_unicast, DynamicProfile

Software information

RTI developed a testing framework specifically designed for discovery benchmarking. This framework was used to perform the tests detailed in this section. This framework is capable of distributing and executing the different DDS entities across the different machines available in RTI’s Performance and Discovery Lab. It also gathers information about discovery time as well as network usage and memory usage.

The Middleware version used to perform these tests is:

RTI Connext DDS 7.3.0 Host and Target Libraries for x64 Linux (x64Linux4gcc7.3.0)

Hardware information

Linux Nodes

Dell R340 Servers (13 Units)
Processor: Intel Xeon E-2278G (3.4-5GHz, 8c/16t, 16MB cache, 2 memory channels @2666MHz)
RAM: 4x 16GB 2666MHz DIMM (64GB RAM)
HD: 480GB SATA SSD
NIC 1: Intel 710 dual port 10Gbps SFP
OS: Ubuntu 20.04 -- gcc 9.3.0

Switch

Dell 2048 -- 10Gbps switch (10Gbps and 1Gbps interfaces)

QoS Used

<?xml version="1.0"?>
<dds xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:noNamespaceSchemaLocation="https://community.rti.com/schema/7.2.0/rti_dds_qos_profiles.xsd">

    <qos_library name="QosLibrary">

        <qos_profile name="FactoryDefault" is_default_participant_factory_profile="true">
            <participant_factory_qos>
                <entity_factory>
                    <autoenable_created_entities>$(autoenable_created_entities)</autoenable_created_entities>
                </entity_factory>
                <!-- <logging>
                    <verbosity>WARNING</verbosity>
                </logging> -->
            </participant_factory_qos>
            <participant_qos>
                <discovery_config>
                    <builtin_discovery_plugins>$(qos_discovery_protocol)</builtin_discovery_plugins>
                </discovery_config>
            </participant_qos>
        </qos_profile>

        <qos_profile name="DynamicProfile_DefaultQoS" base_name="QosLibrary::FactoryDefault">
            <participant_qos>
                <!-- This does not affect performance, but it is needed for > 1000 participants -->
                <wire_protocol>
                    <rtps_well_known_ports>
                        <domain_id_gain>500</domain_id_gain>
                    </rtps_well_known_ports>
                </wire_protocol>
                <!-- To make the test a bit more fair -->
                <transport_builtin>
                    <mask>UDPv4</mask>
                </transport_builtin>
                <property>
                    <value>
                        <element>
                            <name>dds.transport.UDPv4.builtin.parent.allow_interfaces_list</name>
                            <value>$(interface_name)</value>
                        </element>
                        <element>
                            <name>dds.transport.UDPv4.builtin.parent.max_interface_count</name>
                            <value>2</value>
                        </element>
                        <element>
                            <name>dds.participant.property_validation_action</name>
                            <value>1</value>
                        </element>
                        <element>
                            <name>dds.transport.UDPv4.builtin.gather_detailed_statistics</name>
                            <value>$(gather_detailed_statistics)</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <qos_profile name="DynamicProfile" base_name="QosLibrary::DynamicProfile_DefaultQoS" is_default_qos="true">
            <participant_qos>
                <resource_limits>
                    <type_object_max_serialized_length>0</type_object_max_serialized_length>
                    <type_code_max_serialized_length>0</type_code_max_serialized_length>
                    <remote_writer_hash_buckets>625</remote_writer_hash_buckets>
                    <remote_reader_hash_buckets>625</remote_reader_hash_buckets>
                    <remote_participant_hash_buckets>625</remote_participant_hash_buckets>
                    <matching_reader_writer_pair_hash_buckets>625</matching_reader_writer_pair_hash_buckets>
                    <matching_writer_reader_pair_hash_buckets>625</matching_writer_reader_pair_hash_buckets>
                </resource_limits>
                <discovery_config>
                    <initial_participant_announcements>5</initial_participant_announcements>
                    <participant_liveliness_lease_duration>
                        <sec>500</sec>
                        <nanosec>0</nanosec>
                    </participant_liveliness_lease_duration>
                    <participant_liveliness_assert_period>
                        <sec>5</sec>
                        <nanosec>0</nanosec>
                    </participant_liveliness_assert_period>
                    <remote_participant_purge_kind>LIVELINESS_BASED_REMOTE_PARTICIPANT_PURGE</remote_participant_purge_kind>
                    <max_liveliness_loss_detection_period>
                        <sec>10</sec>
                        <nanosec>0</nanosec>
                    </max_liveliness_loss_detection_period>
                </discovery_config>
                <property>
                    <value>
                        <element>
                            <name>dds.transport.UDPv4.builtin.recv_socket_buffer_size</name>
                            <value>5048576</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <qos_profile name="Unicast_10Gbps_lab_snippet">
            <participant_qos>
                <discovery>
                    <initial_peers>
                        <element>$(initial-peers)</element>
                    </initial_peers>
                    <multicast_receive_addresses></multicast_receive_addresses>
                </discovery>
            </participant_qos>
        </qos_profile>

        <qos_profile name="Unicast_1Gbps_lab_snippet">
            <participant_qos>
                <discovery>
                    <initial_peers>
                        <element>$(initial-peers)</element>
                    </initial_peers>
                    <multicast_receive_addresses></multicast_receive_addresses>
                </discovery>
            </participant_qos>
        </qos_profile>

        <qos_profile name="DynamicProfile_unicast_cds" base_name="QosLibrary::DynamicProfile">
            <participant_qos>
                <transport_builtin>
                    <mask>UDPv4</mask>
                </transport_builtin>
                <discovery>
                    <initial_peers>
                        <element>rtps@udpv4://$(CDS_IP):7400</element>
                    </initial_peers>
                    <multicast_receive_addresses></multicast_receive_addresses>
                </discovery>
            </participant_qos>
        </qos_profile>

        <qos_profile name="StaticProfile" base_name="QosLibrary::DynamicProfile">
            <participant_qos>
                <discovery_config>
                    <builtin_discovery_plugins>SPDP</builtin_discovery_plugins>
                </discovery_config>
                <property>
                    <value>
                        <element>
                            <name>dds.discovery.endpoint.lbediscovery.library</name>
                            <value>rtilbedisc</value>
                        </element>
                        <element>
                            <name>dds.discovery.endpoint.lbediscovery.create_function</name>
                            <value>DDS_LBEDiscoveryPlugin_create</value>
                        </element>
                        <element>
                            <name>dds.discovery.endpoint.load_plugins</name>
                            <value>dds.discovery.endpoint.lbediscovery</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <!-- Security -->
        <qos_profile name="DynamicProfileSecurity" base_name="QosLibrary::DynamicProfile">
            <participant_qos>
                <property>
                    <value>
                        <element>
                            <name>com.rti.serv.load_plugin</name>
                            <value>com.rti.serv.secure</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.library</name>
                            <value>nddssecurity</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.create_function</name>
                            <value>RTI_Security_PluginSuite_create</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.authentication.ca_file</name>
                            <value>resources/secure/certAuthority/$(discovery_security_algo)/ca/$(discovery_security_algo)RootCaCert.pem</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.authentication.private_key_file</name>
                            <value>resources/secure/certAuthority/$(discovery_security_algo)/identities/$(discovery_security_algo)Peer01Key.pem</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.authentication.certificate_file</name>
                            <value>resources/secure/certAuthority/$(discovery_security_algo)/identities/$(discovery_security_algo)Peer01Cert.pem</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.access_control.permissions_authority_file</name>
                            <value>resources/secure/certAuthority/$(discovery_permissions_authority_file_algo)/ca/$(discovery_permissions_authority_file_algo)RootCaCert.pem</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.access_control.governance_file</name>
                            <value>resources/secure/certAuthority/$(discovery_security_algo)/governances/signed_governance_$(security_governance).xml</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.access_control.permissions_file</name>
                            <value>resources/secure/certAuthority/$(discovery_security_algo)/signed_myPermissions.xml</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.authentication.key_establishment_algorithm</name>
                            <value>auto</value>
                        </element>
                        <element>
                            <name>dds.participant.trust_plugins.authentication_timeout.sec</name>
                            <value>$(discovery_security_authentication_timeout)</value>
                        </element>
                        <element>
                            <name>dds.participant.trust_plugins.authentication_request_delay.sec</name>
                            <value>$(discovery_security_authentication_request_delay)</value>
                        </element>
                        <element>
                            <name>dds.participant.trust_plugins.authentication_request_timeout.sec</name>
                            <value>$(discovery_security_authentication_request_timeout)</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.authentication.enable_custom_algorithms</name>
                            <value>true</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <!-- Security Unicast 10Gbps-->
        <qos_profile name="DynamicProfileSecurity_unicast" base_name="QosLibrary::DynamicProfileSecurity">
            <base_name>
                <element>QosLibrary::Unicast_10Gbps_lab_snippet</element>
            </base_name>
        </qos_profile>

        <!-- Security Unicast 10Gbps-->
        <qos_profile name="DynamicProfileSecurity_unicast_enp1s0f0" base_name="QosLibrary::DynamicProfileSecurity_unicast">
        </qos_profile>

        <!-- Security Unicast 1Gbps -->
        <qos_profile name="DynamicProfileSecurity_unicast_eno1" base_name="QosLibrary::DynamicProfileSecurity">
            <base_name>
                <element>QosLibrary::Unicast_1Gbps_lab_snippet</element>
            </base_name>
        </qos_profile>

        <!-- Security HMAC ONLY -->
        <qos_profile name="DynamicProfileSecurity_HMAC" base_name="QosLibrary::DynamicProfile">
            <participant_qos>
                <property>
                    <value>
                        <element>
                            <name>com.rti.serv.load_plugin</name>
                            <value>com.rti.serv.secure</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.library</name>
                            <value>nddssecurity</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.create_function</name>
                            <value>RTI_Security_PluginSuite_create</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.hmac_only.enabled</name>
                            <value>1</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.hmac_only.cryptography.key</name>
                            <value>str:SecretKey</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <!-- Security + PSK-->
        <qos_profile name="DynamicProfileSecurity_PSK" base_name="QosLibrary::DynamicProfileSecurity">
            <participant_qos>
                <discovery_config>
                    <default_domain_announcement_period>
                        <sec>DURATION_INFINITE_SEC</sec>
                        <nanosec>DURATION_INFINITE_NSEC</nanosec>
                    </default_domain_announcement_period>
                </discovery_config>
                <property>
                    <value>
                        <element>
                            <name>com.rti.serv.secure.cryptography.rtps_protection_preshared_key</name>
                            <!-- <value>str:1:SecretKey</value> -->
                            <value>data:,1:SecretKey</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

        <!-- LW Security + PSK -->
        <qos_profile name="DynamicProfileLWS_PSK" base_name="QosLibrary::DynamicProfile">
            <participant_qos>
                <discovery_config>
                    <default_domain_announcement_period>
                        <sec>DURATION_INFINITE_SEC</sec>
                        <nanosec>DURATION_INFINITE_NSEC</nanosec>
                    </default_domain_announcement_period>
                </discovery_config>
                <property>
                    <value>
                        <element>
                            <name>com.rti.serv.load_plugin</name>
                            <value>com.rti.serv.secure</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.library</name>
                            <value>nddslightweightsecurity</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.create_function</name>
                            <value>RTI_SecurityLightweight_PluginSuite_create</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.cryptography.rtps_protection_preshared_key</name>
                            <!-- <value>str:1:SecretKey</value> -->
                            <value>data:,1:SecretKey</value>
                        </element>
                        <element>
                            <name>com.rti.serv.secure.cryptography.rtps_protection_preshared_key_algorithm</name>
                            <value>$(lws_psk_algorithm)</value>
                        </element>
                    </value>
                </property>
            </participant_qos>
        </qos_profile>

    </qos_library>
</dds>