Stellio load testing

This project aims to provide some load tests for Stellio (or any NGSI-LD API compliant context broker)

Setup

• Follow instructions on https://k6.io/docs/extensions/guides/build-a-k6-binary-using-go/ to setup Go and xk6.

• Build a k6 binary with dotenv and TimescaleDB extensions

xk6 build latest --with github.com/szkiba/xk6-dotenv --with github.com/grafana/xk6-output-timescaledb

• If you don't want to save results in TimescaleDB (and see them in a Grafana dashboard), build the k6 binary with the following command

xk6 build latest --with github.com/szkiba/xk6-dotenv

• Start docker-compose config with Timescale and Grafana if you have compiled the binary with this extension

docker-compose up -d && docker-compose logs -f --tail=100

How to run a load test

For a script to run:

• The env variable STELLIO_HOSTNAME needs to be set, configure it in the .env file
• The connection to Timescale has to be passed in run.sh if you configured this extension
• A script typically has default values for the number of VUs, iterations,... but they can be overriden on the CLI (among other ways)

An util script is available to more easily launch a load test script:

# first parameter is the name of the script to launch
# second parameter is the number of VUs
# third parameter is the number of iterations
# fourth parameter is the max duration of the test (without the setup phase)
./run.sh src/tests/create-entities.js 10 10000 10m

If needed to set a specific parameter for a script, it can be passed as an environment variable, e.g.,:

INITIAL_NUMBER_OF_ENTITIES=5 ./run.sh src/tests/partial-attribute-update-entities.js 10 10000 10m

List of ready to use tests

• Create entities

./run.sh src/tests/create-entities.js 10 10000 10m

• Partial attribute update

INITIAL_NUMBER_OF_ENTITIES=10 ./run.sh src/tests/partial-attribute-update-entities.js 10 10000 10m

• Update attributes

INITIAL_NUMBER_OF_ENTITIES=10 ./run.sh src/tests/update-attributes.js 10 10000 10m

• Query entities by type and property value

INITIAL_NUMBER_OF_ENTITIES=1000 INITIAL_NUMBER_OF_TYPES=5 ./run.sh src/tests/query-entities-by-type-and-property-value.js 10 10000 15m

• Query entities by type and relationship object

INITIAL_NUMBER_OF_ENTITIES=1000 INITIAL_NUMBER_OF_TYPES=5 INITIAL_NUMBER_OF_RELATIONSHIPS=10 ./run.sh src/tests/query-entities-by-type-and-relationship-object.js 10 10000 15m

• Retrieve temporal evolution of an entity

INITIAL_NUMBER_OF_ENTITIES=10 INITIAL_NUMBER_OF_INSTANCES=100 ./run.sh src/tests/retrieve-temporal-evolution-of-an-entity.js 10 10000 30m

• Retrieve temporal evolution of an entity with temporal values

INITIAL_NUMBER_OF_ENTITIES=10 INITIAL_NUMBER_OF_INSTANCES=100 TEMPORAL_REPRESENTATION=temporal ./run.sh src/tests/retrieve-temporal-evolution-of-an-entity.js 10 10000 30m

• Retrieve temporal evolution of an entity (aggregated values)

INITIAL_NUMBER_OF_ENTITIES=10 INITIAL_NUMBER_OF_INSTANCES=100 TEMPORAL_REPRESENTATION=aggregated ./run.sh src/tests/retrieve-temporal-evolution-of-an-entity.js 10 10000 30m

• Query temporal evolution by type and attrs

INITIAL_NUMBER_OF_ENTITIES=10 INITIAL_NUMBER_OF_INSTANCES=100 ./run.sh src/tests/query-temporal-evolution-by-type-and-attrs.js 10 10000 15m

• Query temporal evolution by type and attrs with temporal values

INITIAL_NUMBER_OF_ENTITIES=10 INITIAL_NUMBER_OF_INSTANCES=100 TEMPORAL_REPRESENTATION=temporal ./run.sh src/tests/query-temporal-evolution-by-type-and-attrs.js 10 10000 15m

Delete a test

In order to not pollute the DB with results of unwanted runs, it is possible to manually delete a test from the DB:

• Connect to the container running the DB

docker exec -it <timescaledb_container> bash

• Connect to the DB

psql -U k6 k6

• Delete the test

delete from samples where tags->>'testid' = '<test_id>';

Extensions

Extensions currently used:

• https://github.com/grafana/xk6-output-timescaledb: send k6 metrics to TimescaleDB in a predefined schema and visualize them in Grafana dashboards
• https://github.com/szkiba/xk6-dotenv: load env vars from a .env file