[TILES-V2-10]: add load testing scripts for tiles database

[pregnantboy]

TL;DR

Added load testing scripts for Postgres database operations with k6 extensions.

What changed?

• Added a .env-example file with Postgres connection string
• Updated the README with instructions for building k6 with extensions (postgres, dotenv, dashboard)
• Updated the k6 binary to support these extensions
• Added several new load testing scripts for Postgres operations:
  • seed_table.js - Creates test tables
  • bulk_write.js - Tests bulk insert operations
  • bulk_read.js - Tests bulk read operations
  • read_action.js - Tests single read operations
  • write_action.js - Tests single write operations
  • update_action.js - Tests update operations
  • test.js - Simple connection test

How to test?

1. Copy .env-example to .env and update with your Postgres connection details
2. Build k6 with extensions using the Docker command in the README:

   docker run --rm -it -e GOOS=darwin -u "$(id -u):$(id -g)" -v "${PWD}:/xk6" \
     grafana/xk6 build \
     --with github.com/grafana/xk6-sql@latest \
     --with github.com/grafana/xk6-sql-driver-postgres@latest \
     --with github.com/grafana/xk6-dashboard@latest\
     --with github.com/szkiba/xk6-dotenv@latest
   

3. Run the test scripts, for example:

   ./k6 run tiles/test.js --out dashboard
   

[pregnantboy]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• [TILES-V2-11]: add unit and integration tests for tiles v2 #1033
• [TILES-V2-10]: add load testing scripts for tiles database #1011 👈 (View in Graphite)
• [TILES-V2-9]: store database type in TableContext on frontend #987
• [TILES-V2-8]: add env vars #986
• [TILES-V2-7]: update tiles actions to use factory class #985
• [TILES-V2-6]: use factory class for queries and mutations, minimise getAllRows payload #977
• [TILES-V2-5]: abstract functions into factory pattern #976
• [TILES-V2-4]: reorganise files and update import paths #975
• [TILES-V2-3]: implement postgres functions for row, column and table operations #974
• [TILES-V2-2]: add new column to table_metadata #973
• [TILES-V2-1]: add another postgres db to docker compose, new env vars #972
• tiles-v2/trunk

This stack of pull requests is managed by Graphite. Learn more about stacking.

[datadog-opengovsg]

Datadog Report

Branch report: tiles-v2/load-tests
Commit report: a960b53
Test service: plumber

✅ 0 Failed, 773 Passed, 0 Skipped, 2m 46.06s Total Time
⬆️ Test Sessions change in coverage: 1 increased (+0.7%)

[cursor-com]

Bug: SQL Syntax Error and Incorrect Result Validation

The script contains two bugs: The SQL query ends with a double semicolon (;;), which is a syntax error. Additionally, it incorrectly uses rowsAffected() to validate the result of a SELECT query. rowsAffected() is intended for DML operations (INSERT, UPDATE, DELETE) and typically returns 0 for SELECT queries, causing the check rowsAffected() === 1 to always fail.

tools/load-tests/tiles/read_action.js#L34-L42

plumber/tools/load-tests/tiles/read_action.js

Lines 34 to 42 in a960b53

	const result = db.exec(`
	SELECT * FROM "public"."load_test_table_1" WHERE "column1" = 'row${Math.floor(
	Math.random() * 1000,
	)}-col1';;
	`)
	// const result = db.exec(`
	// SELECT 1 FROM "public"."load_test_table_${exec.vu.idInInstance}";
	// `)
	check(result, 'is added', (r) => r.rowsAffected() === 1)

tools/load-tests/tiles/test.js#L13-L14

plumber/tools/load-tests/tiles/test.js

Lines 13 to 14 in a960b53

	const result = db.exec(`SELECT 1 as connection_test`)
	console.log(result.rowsAffected())

Fix in Cursor

---

Bug: Table Name Mismatch Causes Load Test Failures

The load test scripts (bulk_write.js, write_action.js, bulk_read.js) use exec.vu.idInInstance for table names, which conflicts with the seed script's use of exec.vu.iterationInInstance. This mismatch causes read, insert, and bulk insert operations to fail due to non-existent tables. The bulk_read.js script also lacks the maxVUs scenario option and has a misleading console.log message about the number of rows read.

tools/load-tests/tiles/bulk_read.js#L9-L38

plumber/tools/load-tests/tiles/bulk_read.js

Lines 9 to 38 in a960b53

	scenarios: {
	contacts: {
	executor: 'constant-arrival-rate',
	duration: '5m',
	rate: 100,
	// It should start `rate` iterations per second
	timeUnit: '10s',
	// It should preallocate 2 VUs before starting the test
	preAllocatedVUs: 100,
	// It is allowed to spin up to 50 maximum VUs to sustain the defined
	// constant arrival rate.
	},
	},
	}
	export default function () {
	const db = sql.open(driver, __ENV.POSTGRES_TILES_URL)
	const i = Math.floor(Math.random() * 30)
	db.exec(`
	SELECT * FROM "public"."load_test_table_${
	exec.vu.idInInstance
	}" ORDER BY "rowId" LIMIT 10000 OFFSET ${i * 10000};
	`)
	console.log(
	`read ${i * 10000} rows in load_test_table_${exec.vu.idInInstance}`,

tools/load-tests/tiles/write_action.js#L39-L42

plumber/tools/load-tests/tiles/write_action.js

Lines 39 to 42 in a960b53

	const result = db.exec(`
	INSERT INTO "public"."load_test_table_${
	exec.vu.idInInstance
	}" ("rowId", "column0", "column1", "column2", "column3", "column4", "column5", "column6", "column7", "column8", "column9") VALUES ${generatedRows

tools/load-tests/tiles/bulk_write.js#L39-L42

plumber/tools/load-tests/tiles/bulk_write.js

Lines 39 to 42 in a960b53

	const result = db.exec(`
	INSERT INTO "public"."load_test_table_${
	exec.vu.idInInstance
	}" ("rowId", "column0", "column1", "column2", "column3", "column4", "column5", "column6", "column7", "column8", "column9") VALUES ${generatedRows

Fix in Cursor

---

Bug: Update Fails Due to Missing ID and Table Name Mismatch

The UPDATE query fails because the hardcoded rowId 'to update' does not exist (other scripts use generated UUIDs), resulting in 0 rows updated. A potential table name mismatch (idInInstance vs iterationInInstance) could also cause the table not to be found. Both issues lead to the check on line 37 failing.

tools/load-tests/tiles/update_action.js#L33-L34

plumber/tools/load-tests/tiles/update_action.js

Lines 33 to 34 in a960b53

	const result = db.exec(`
	UPDATE "public"."load_test_table_${exec.vu.idInInstance}" SET "column2" = 'updated' WHERE "rowId" = 'to update';

Fix in Cursor

---

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