Cypress "Chromium Renderer process just crashed" /dev/shm in CI

Chrome stores shared memory in /dev/shm, which defaults to 64MB in many Docker containers. When it fills, the renderer crashes and Cypress reports the renderer process crashed. Enlarging /dev/shm or disabling its use resolves it.

What this error means

Specs fail with "We detected that the Chromium Renderer process just crashed", often clustered on heavier pages, only in containerized CI and never locally.

cypress

We detected that the Chromium Renderer process just crashed.

This is the equivalent to seeing the 'sad face' when Chrome dies.

To learn more about why this can happen, read:
https://on.cypress.io/renderer-process-crashed

Common causes

Default 64MB /dev/shm is too small

Containers often cap /dev/shm at 64MB; Chrome exhausts it on busy pages and the renderer crashes.

Many heavy DOM specs in one process

Memory-heavy pages compound the shared-memory pressure until the renderer dies mid-run.

How to fix it

Enlarge /dev/shm

Run the container with a larger shared-memory mount so Chrome does not run out.

Terminal

docker run --shm-size=2g cypress/included:13.15.0

Disable /dev/shm usage in the browser

When you cannot enlarge /dev/shm, tell Chrome not to use it via a launch flag.

cypress.config.js

on('before:browser:launch', (browser, opts) => {
  opts.args.push('--disable-dev-shm-usage');
  return opts;
});

How to prevent it

Provision --shm-size=2g (or more) for Cypress containers.
Add --disable-dev-shm-usage when the mount cannot be enlarged.
Split heavy suites to reduce per-process memory pressure.