[BUG] Capacity overflowing uint32

[Alfus]

Description

I am trying to use bytes as my cost function, but the policy is silently casting the capacity from an int to a uint32. This effectively makes the max cache size 4GB, where values over that overflow and get a ~random size

To Reproduce

Set the capacity to math.MaxUint32 + 1 every entry will be rejected.

Expected behavior

Normal caching (or at least an error)

Environment

• OS: macos

Additional context

[Alfus]

otter/internal/core/cache.go

Line 142 in 9d61c67

policy: s3fifo.NewPolicy[K, V](uint32(c.Capacity)),

[maypok86]

Okay, I'll fix it a bit later. But I should immediately note that storing 4 GB of data in an onheap cache is hardly a good idea.

[Alfus]

I have 32GB of RAM to use as a ~block cache for s3/gcs, why is >4GB a bad idea?

[maypok86]

Check it out, but there is a possibility that the garbage collector will run with long pauses due to the many entries that it has to scan every cycle. Usually onheap caches are not very large. Up to 10 million entries or 1 GB (approximate numbers).

[maypok86]

You can store more, but it's worth checking the behavior on your data.

[Alfus]

My chunk size is 4-8MB, so 4GB ends up being ~1k entries of ~[]bytes.

[maypok86]

being ~1k entries of ~[]bytes.

Oh, well, then everything should be fine. I should have warned you, sorry.

[maypok86]

@Alfus I believe I've fixed it. Please try it from the main branch, if everything is fine, then I will release a new version tomorrow.