Crash with node alpine but not node slim

[daveisfera]

Our application crashes V8 when running with node:6.9.2-alpine but not with node:6.9.2-slim. Is there anything I can do to help diagnose the cause of this issue?

[LaurentGoderre]

What happens when you run docker logs?

[daveisfera]

There's nothing in the logs for the container, but this is in the dmesg logs on the host:

[19594787.401624] V8 WorkerThread[8217]: segfault at 7f4d0e74eff8 ip 00007f4d0d597d8e sp 00007f4d0e74f000 error 6 in node[7f4d0ccdc000+18b6000]

[LaurentGoderre]

Is there a way you can share the Dockerfile?

[daveisfera]

The Dockerfile itself is pretty simple but I can't share our code so it wouldn't be much use. If I had an idea of where to start looking, I'd work on creating a stand alone, minimal reproducer, but I'm not sure where to even start with that since I'm not sure what's causing the crash.

[chorrell]

It would be good to know what modules you are using in your app. This could be a v8 issue under Alpine, given that your app works fine using the slim variant (debian).

[pesho]

I'd work on creating a stand alone, minimal reproducer, but I'm not sure where to even start with that since I'm not sure what's causing the crash.

You can try to isolate if a specific require/import or other action in your application is causing the crash.

[LaurentGoderre]

Do you use node-gyp in your alpine Dockerfile?

[daveisfera]

Not in the container that's crashing.

[daveisfera]

I've been unable to make a minimal reproducer because the point at which it crashes jumps around in our code, but it only happens when using ajv to validate GeoJSON using the schema from http://json.schemastore.org/geojson and that's the most I've been able to isolate the issue.

[LaurentGoderre]

Is any of the dependencies using pre-built binaries, those sometimes have issues. I think the ecosystem in general isn't familiar with alpine and musl yet so a lot of the prebuilt binaries don't work in alpine and you sometimes have to compile them from source.

[daveisfera]

As far as I can tell, ajv and it's dependencies are pure Javascript so I don't believe it's an issue with pre-built binaries.

If I removed the GeoJSON validation and just ran more data through, then the crash still happens. I also ran the tests from ajv against the Alpine base image in hopes that it would reveal something, but all of the tests passed except for one that relies on an unavailable module (see ajv-validator/ajv#404).

[daveisfera]

I'm not sure what fixed the issue, but I can no longer reproduce this.