x/playground: Game Of Life play example fails to compile on golang.org due to out of memory error

[epeay]

Please answer these questions before submitting your issue. Thanks!

What version of Go are you using (go version)?

1.11.1 as reported by the server.

Does this issue reproduce with the latest release?

Not relevant. Server-side issue.

What operating system and processor architecture are you using (go env)?

Not relevant. Server-side issue.

What did you do?

https://play.golang.org/p/jibIOKi7wqW

What did you expect to see?

The game of life

What did you see instead?

go tool compile: exit status 2
fatal error: runtime: out of memory

The example does run (I tested on 1.10.3 locally). It just doesn't run on the golang.org site, likely due to a restriction on the back-end environment that's doing the compilation.

If the environment is what it's supposed to be (whatever that is), and the example just needs to be tweaked to use less memory, I'd be interested in taking care of that and sending a PR.

[ALTree]

and the example just needs to be tweaked to use less memory,

I very much doubt this is the case. I suspect this is related to the bad caching on nondetermistic error issue the playground had: #26926. Not sure why it's still happening, in theory it should be fixed. I don't know if the fixed playground was deployed.

[agnivade]

/cc @broady @andybons

[ysmolski]

Right now playground checks errors in the response.Events slice, that is for successfully built programs:

// Runtime error strings that will not be cached if found in an Event message.
var nonCachingRuntimeErrors = []string{"out of memory", "cannot allocate memory"}

But in our case it failed to build the program , response.Errors contains OOM message, response was cached and returned. We should do the same check for response.Errors too.

[andybons]

@katiehockman

[katiehockman]

Thanks for the extra context @ysmolsky. Looks like the original change fixed some issues, but not all.

@ALTree to answer your question, yes it was deployed shortly after the change was merged.

I'll assign this to myself and hopefully send out the fix very soon.

[gopherbot]

Change https://golang.org/cl/144297 mentions this issue: playground: prevent caching memory-related compile time errors

[dmitshur]

Commit golang/playground@d134d7d has been deployed now. Please let us know if the issue occurs again.