Ristretto is a fast, concurrent cache library using a TinyLFU admission policy and Sampled LFU eviction policy.

The motivation to build Ristretto comes from the need for a contention-free cache in Dgraph.

package main

import (
	"fmt"
	"time"

	"github.com/dgraph-io/ristretto"
)

func main() {
	// create a cache instance
	cache, err := ristretto.NewCache(&ristretto.Config{
		NumCounters: 1000000 * 10,
		MaxCost:     1000000,
		BufferItems: 64,
	})
	if err != nil {
		panic(err)
	}

	// set a value
	cache.Set("key", "value", 1)

	// wait for value to pass through buffers
	time.Sleep(time.Second / 100)

	// get a value, given a key
	value, found := cache.Get("key")
	if !found {
		panic("missing value")
	}

	fmt.Println(value)

	// delete a value, given a key
	cache.Del("key")
}

The benchmarks can be found in https://github.com/dgraph-io/benchmarks/tree/master/cachebench/ristretto

This trace is described as "disk read accesses initiated by a large commercial search engine in response to various web search requests."

This trace is described as "a database server running at a commercial site running an ERP application on top of a commercial database."

This trace demonstrates a looping access pattern.

This trace is described as "references to a CODASYL database for a one hour period."

All throughput benchmarks were ran on an Intel Core i7-8700K (3.7GHz) with 16gb of RAM.