Cache seems to return unrelated values after a while

[bcomnes]

I apologize in advance for not having this fully pinned down, but after updating to version 7.0.0-7.3.0, it seems as though the cache starts returning values for unrelated cache keys, after a while under moderate load (~5 minutes).

This is my cache:

const cache = new LRU({
  max: 10000,
  maxAge: 1000 * 60 * 20, // 20 mins,
  updateAgeOnGet: false
})

And these keys:

function getCacheKey ({
  access_token,
  refresh_token,
  purchase_id,
  file_id
}) {
  return [access_token, refresh_token, purchase_id, file_id].join(';')
}

Seem to start returning value from these keys:

function getOtherCacheKey ({
  access_token,
  refresh_token,
  purchase_id,
  proxyFiles,
  incomingHost
}) {
  return ['rss', access_token, refresh_token, purchase_id, proxyFiles, incomingHost].join(';')
}

(where the arguments are url escaped strings)

I haven't been able to reproduce it locally yet (though it does reliable begin under moderate production load), but given the delay it seems to have a 'something filling up'ness to it.

The other idea is that maybe the keys are a little long. Are there new restrictions on string keys in version 7?

Usage is limited to simple get/set, and I updated the config to match the what the migration guide recommended.

[HitkoDev]

Can confirm, in the new version cache starts returning random values after a couple of gets / sets.

For now I upgraded to v6, hope this gets resolved soon.

[isaacs]

Can you share any more details about how you're using it? I have a lot of tests where I fill up the cache to the point of eviction, that sounds really strange.

[isaacs]

There is not a limit on string length. Anything that worked before should work now, they're just keys in a map.

[HitkoDev]

https://stackblitz.com/edit/node-wccxgj?file=index.js There you go, a quick repro

[isaacs]

I got a fix. Will ship and backport to 7.x versions within the hour. Sorry for the hassle.

[isaacs]

Fixed with a patch on all 7.x minors, and deprecated all affected versions.

[bcomnes]

Thanks @HitkoDev for isolating the issue, and thanks @isaacs for the fix (and faster algorithm)!

[bcomnes]

Been running the working version of 7 in production and it does speed up cache hits. Not that 6 wasn't doing great, but its fun to see the difference. Basically, uncached results are slow... but when it is cached, it's spending less time returning cached results.