tlru

Package tlru implements TLRU (Time Aware Least Recently Used) cache for Go.

Features:

• Uses generics for type-safety
• Memory-backed
• Safe for concurrent use
• No background threads

go get github.com/ammario/tlru@master

Examples

Basic example:

// This cache can store up to 100 values.
c := tlru.New[string](tlru.ConstantCost[int], 100)
c.Set("dog", 3.14, time.Second)

// 3.14, ~time.Now().Add(time.Second), true
v, deadline, ok := c.Get("dog")

Dynamic costs:

// This cache can store up to 100 bytes.
c := New[string](
    func(v string) int {
        return len(v)
    },
    100,
)
c.Set("some_key", "some value", time.Minute)

Eviction

Cache eviction occurs during:

• Calls to Set()
• Calls to Evict()
• Calls to Get() (for that key only)

Cache eviction is fast because the LRU and TTL indices are sorted. In most cases, a call to the evictor only touches a few entries. Calling Evict() directly is usually unnecessary.

Benchmarks

goos: darwin
goarch: amd64
pkg: github.com/ammario/tlru
cpu: VirtualApple @ 2.50GHz
Benchmark_TLRU_Get-10    	 7117467	       141.9 ns/op
Benchmark_TLRU_Set-10    	 1222298	       990.9 ns/op