Reached heap limit Allocation failed - JavaScript heap out of memory

[west juniper]

Hi, a few days ago I started making some content changes, and after building the site, it never completed the build anymore. Just out of nowhere, the build starts failing. I have tried a lot of solutions on the internet that did not work out unfortunately. I think it has something to do with any package that has updated, however I cannot verify this, or don't know how.

What I tried:

1. Tried adding this code block in my nuxt.config.ts (with NODE_ENV set to production)

  postcss: {
    plugins: {
      tailwindcss: {},
      autoprefixer: {},
      cssnano:
        process.env.NODE_ENV === 'production'
         ? { preset: ['default', { discardComments: { removeAll: true } }] }
            : false, // disable cssnano when not in production
     },
  }

2. Tried adding NODE_OPTIONS –max-old-space-size=4096 in .env

Both solutions do not work. This error is both on my localhost with pnpm run build, and on the netlify hosting when it builds the site.

Build (error)log added

[golden shadow]

Hi @west juniper. I'm kapa.ai, your friendly support bot. I will try to answer your question by searching through the knowledge base. :wave:

---

I can see you're experiencing a JavaScript heap memory error during your Nuxt build process. This is a common issue when building large Nuxt applications, and several of the knowledge sources provide relevant information about this problem.

Understanding the Issue

The "Reached heap limit Allocation failed - JavaScript heap out of memory" error occurs when Node.js runs out of memory during the build process. This is particularly common with large Nuxt applications that have many dependencies or complex components.

Potential Solutions

Based on the knowledge sources, here are some approaches that might help:

1. Downgrade Node.js Version

One of the knowledge sources indicates that downgrading to Node.js v20 might help as a workaround for memory leaks in newer Node versions:

"Confirming no leaks on v20.9.0 LTS." Github Issue #30995

2. Increase Node.js Memory Limit

You mentioned trying NODE_OPTIONS --max-old-space-size=4096, but there might be issues with how it was implemented:

• Make sure there's no typo in the environment variable (should be two dashes before max-old-space-size)
• Try increasing the value further (8192 or higher if your system has enough RAM)
• Ensure the environment variable is properly set for both local and Netlify environments

For Netlify specifically, you can set this in the Netlify UI under site settings > Build & deploy > Environment variables.

3. Check for Problematic Dependencies

Some specific modules have been identified as potential culprits:

"After some research and tests I did a conclusion that problem may be with h3-compression dependency on ^0.3.2 version (at least after it's removal everything if fine again)." Stack Overflow Post #78532075

"@nuxt/scripts is also the culprit in my app, with version 0.11.5 - but only if using useScriptMetaPixel." Github Issue #14168

4. Disable Devtools

One solution mentioned in the knowledge sources:

"I've narrowed our issue down to a combination of both having devtools enabled and the existance of .output/server/node_modules. If I either delete that folder or disable devtools via devtools: { enabled: false } then the error goes away." Github Issue #12376

Try adding this to your nuxt.config.ts:

export default defineNuxtConfig({
  devtools: { enabled: false },
  // your other config
})

5. Clean Build Cache

Try removing the .nuxt, .output, and node_modules directories, then reinstall dependencies and rebuild:

rm -rf .nuxt .output node_modules
npm install # or pnpm install
npm run build # or pnpm run build

Conclusion

Memory issues during Nuxt builds can be complex and might require a combination of approaches. If the above solutions don't work, you might need to analyze your application for memory leaks or consider splitting your application into smaller chunks using dynamic imports to reduce the memory footprint during build time.

Note: you can ask me a follow up question by @ mentioning me again :speech_balloon:

@west juniper Kapa.ai is still learning and improving, please let me know how I did by reacting below.

[west juniper]

No luck 😦

[lucid kraken]

It fails on prerender, are you sure there are no infinite loops in your code?

I stumbled upon very similar error today when coding minimal reproduction. My code was triggering $fetch('/bad/url') on / (could also be done in plugin). Since I did not have special 404 handler, it attempted to fetch home page, which in turn fetched /bad/url and so on, in a loop. This would ultimately cause stack size to be exceeded.

If not, git bisect the changes to see when it was introduced exactly, commit after commit