Paraller Excution in PlayWright

Parallel Execution in Playwright with Python

Automation test suites can become very large as the project grows. Running tests sequentially can take a lot of time. Playwright supports parallel execution which allows multiple tests to run simultaneously.

Parallel execution helps reduce total test execution time and provides faster feedback during CI/CD pipelines.

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What is Parallel Execution?

Parallel execution means running multiple tests at the same time instead of executing them one by one.

• Test 1 running on Chrome
• Test 2 running on Firefox
• Test 3 running on WebKit

All tests execute together which significantly reduces overall test execution time.

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Install Parallel Execution Plugin

Playwright Python projects commonly use Pytest. To enable parallel execution we install the pytest-xdist plugin.

pip install pytest-xdist

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Run Tests in Parallel

You can run tests in parallel using the -n option.

pytest -n 4

This command will run tests using 4 parallel workers.

You can also automatically use all CPU cores.

pytest -n auto

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Run Single Test in Multiple Browsers

Sometimes we need to verify a single test case across multiple browsers. Playwright allows this using pytest parameterization.

import pytest

@pytest.mark.parametrize("browser_name", ["chromium", "firefox", "webkit"])
def test_google(playwright, browser_name):

    browser = getattr(playwright, browser_name).launch()

    page = browser.new_page()

    page.goto("https://google.com")

    print(page.title())

    browser.close()

This single test will run on:

• Chromium (Chrome)
• Firefox
• WebKit (Safari engine)

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Run Multiple Tests in Multiple Browsers

In real automation projects we usually have multiple test cases. These tests can run across multiple browsers in parallel.

import pytest

@pytest.mark.parametrize("browser_name", ["chromium", "firefox"])
def test_google(playwright, browser_name):

    browser = getattr(playwright, browser_name).launch()

    page = browser.new_page()

    page.goto("https://google.com")

    assert "Google" in page.title()

    browser.close()


@pytest.mark.parametrize("browser_name", ["chromium", "firefox"])
def test_bing(playwright, browser_name):

    browser = getattr(playwright, browser_name).launch()

    page = browser.new_page()

    page.goto("https://bing.com")

    assert "Bing" in page.title()

    browser.close()

Run the tests using:

pytest -n 4

The framework will run multiple tests across multiple browsers in parallel.

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Benefits of Parallel Execution

• Reduces test execution time
• Faster CI/CD pipeline execution
• Supports cross-browser testing
• Efficient use of CPU resources
• Faster feedback for developers

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Parallel Execution Summary

Feature	Command / Method	Description
Install Plugin	pip install pytest-xdist	Enables parallel execution
Run Parallel Tests	pytest -n 4	Runs tests using 4 workers
Auto Workers	pytest -n auto	Uses all available CPU cores
Single Test Multiple Browser	pytest.mark.parametrize	Run one test across browsers
Multiple Tests Multiple Browser	pytest + parametrize	Run many tests across browsers

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Conclusion

Parallel execution is an important feature in modern automation frameworks. By combining Playwright, Pytest, and pytest-xdist, testers can run multiple tests across browsers simultaneously.

This approach significantly reduces execution time and improves CI/CD performance.