DDS Qos Optimization

DDS Qos Optimization helps set up FastDDS publishers and subscribers on multiple hosts.

Prerequisite

• FastDDS installed on all hosts (Physical Machines, VMs, Containers).

  Install in the same directory on all hosts.

  You can refer to Linux installation from binaries

How to use

1. Set up host(Physical Machines, VMs, Containers) configurations
   • $ cd DDS-QoS-Optimization/source
   • $ cp inventory.yaml.Example inventory.yaml
   • Fill in hosts IP, port, username, and path to ssh private key.
2. Set up experiment case configurations
   • $ cd DDS-QoS-Optimization/source/config
   • $ mkdir case-[number]
   • $ cp configs.yaml.Example case-[number]/configs.yaml
   • Edit configs.yaml (Details explained in Experiment Case Configuration)
3. Run the experiment case
   • $ cd DDS-QoS-Optimization/source/script
   • $ bash run.sh [number] [number-of-trials] [sleep-time]
4. Get number of messages sent/received and loss rate
   • $ cd DDS-QoS-Optimization/source/script
   • $ python3 statistics.py -t [number-of-trials] -c [number]

How system works

By executing playbook.yml, you got several stages:

1. Set up the experiment
2. Set up publishers and subscribers on each hosts
   • By create.sh generated by template in stage 1, here we specify name, topic, #messages, sending rate to create pubs and subs.
   • But as for now, all publishers aren't sending anything yet.
3. Make all publishers start sending messages
   • Set .flag on all hosts to 1, so that all publishers start sending.
4. Collect publisher/subscriber logs from hosts to controlNode

Experiment Case Configuration

What need to be configured

1. Case number
2. Publisher and Subscriber settings

Detail explained

• repoUrl: Git remote URL of DDS-QoS-Optimization
• fastddsPath: Absolute path to directory where FastDDS installed
• repoPath: Absolute path to where you want DDS-QoS-Optimization cloned on hosts by playbook.yml
• case_num: Experiment Case number
• transport: Currently not working, default transport in FastDDS is used.
• controlNodeBasePath
  • controlNode: where you execute playbook.yml
  • Absolute path to DDS-QoS-Optimization on controlNode.
• wait_for_timeout: Wait for publishers sent all messages in this Experiment Case
• topicPrefix: Set up a prefix for each topic
• host[number]:
  • [number] depends on how many hosts you got
  • in each host[number], you can append an entity (publisher or subscriber)
  • publisher
    • in format: p[number]:t[number]:[number-of-messages]:[sending-rate]
    • e.g., p1:t1:10000:1000
  • subscirber
    • in format: s[number]:t[number]:[number-of-messages]
    • e.g., s1:t1:10000
  • Make sure the number of messages received by subscriber matches that from publisher to the same topic.