ttlcache

About

ttlcache – is a simple and efficient in-memory key value storage with TTL for each record.

The key is of uint64 type. Library provides wrappers for common types:

• IntKey
• ByteKey
• Int8Key
• Uint8Key
• Int16Key
• Uint16Key
• Int32Key
• Uint32Key
• Int64Key
• Uint64Key
• BytesKey ([]byte)
• StringKey
• AnyKey (interface{})

AnyKey is not suitable for very intensive usage. Consider writing your own hash function if your keys are complex types, and you faced performance degradation.

Installation

go get -u github.com/cheshir/ttlcache

Usage

package main

import (
    "github.com/cheshir/ttlcache"
)

const (
    minute = 60 * time.Second
    hour = 60 * minute
)

func main() {
    // How often we need to stop the world and remove outdated records.
	resolution := minute

	cache := ttlcache.New(resolution)
	cache.Set(ttlcache.StringKey("some key"), "value", hour)
	value, ok := cache.Get(ttlcache.StringKey("some key"))
	if !ok {
		// there is no record with key "some key" in the cache. Probably it has been expired.
	}

	fmt.Println(value.(string)) // This is necessary type assertion, because returned value is of interface{} type.
}

Performance

If you're interested in benchmarks you can check them in repository. Just play with numbers and types and check that library is suitable for your purposes.

go test -bench=. -benchmem

For those of us who wants to get some numbers without downloading unknown stuff (MacBook Pro 16"):

BenchmarkCache_Set-16            8755802               122 ns/op               8 B/op          0 allocs/op
BenchmarkCache_Get-16           57474564               19.6 ns/op              0 B/op          0 allocs/op