Memory leak

[runk]

Hello, I want to draw your attention to a memory leak problem that's reported for maxmind I maintain: runk/node-maxmind#740

The only change between "good" and "bad" version of maxmind is the version upgrade of tiny-lru in September. Releases with notes: https://github.com/runk/node-maxmind/releases

Do you have any clues what this could be?

[avoidwork]

Yes, a bug in their code.

[avoidwork]

I looked at your code briefly, but it's hard to follow where you're using the cache between the modules.

If you look at 11.1.2...11.2.0 the only difference that could cause your behavioral change is making 'has()' public, which historically is known to be a problem if anything external makes an assumption on the boolean it returns without considering lazy expiration.

11.1.2 to 11.2.0 exposes 'has()' and exports the class.

[avoidwork]

in 11.1.2 a statement was deleted which may be the cause of the leak if it leaves orphans in ram. it doesn't have test coverage.

11.1.1...11.1.2#diff-79389319fa7fe3ff2ff6e0d5c97a626b12d8a2c72323e8ad210f43c8f98b1d60L129

[avoidwork]

Fix has shipped in 11.2.1.

[avoidwork]

Test added at https://github.com/avoidwork/tiny-lru/blob/master/test/lru.js#L124-L130

[runk]

Thanks for looking into!