【golang】GCache Supports expirable LFU, LRU and ARC

1 特性

• Supports expirable Cache, LFU, LRU and ARC.

• Goroutine safe.

• Supports event handlers which evict, purge, and add entry. (Optional)

• Automatically load cache if it doesn't exists. (Optional)

2 使用

Loading Cache

If specified LoaderFunc, values are automatically loaded by the cache, and are stored in the cache until either evicted or manually invalidated.

func main() {
  gc := gcache.New(10).
    LRU().
    LoaderFunc(func(key interface{}) (interface{}, error) {
      return "value", nil
    }).
    Build()
  v, _ := gc.Get("key")
  // output: "value"
  fmt.Println(v)
}

GCache coordinates cache fills such that only one load in one process of an entire replicated set of processes populates the cache, then multiplexes the loaded value to all callers.

Event handlers

Event handler for evict the entry.

func main() {
  gc := gcache.New(2).
    EvictedFunc(func(key, value interface{}) {
      fmt.Println("evicted key:", key)
    }).
    Build()
  for i := 0; i < 3; i++ {
    gc.Set(i, i*i)
  }
}

Added handler

Event handler for add the entry.

func main() {
  gc := gcache.New(2).
    AddedFunc(func(key, value interface{}) {
      fmt.Println("added key:", key)
    }).
    Build()
  for i := 0; i < 3; i++ {
    gc.Set(i, i*i)
  }
}

Expirable cache

func main() {
  // LRU cache, size: 10, expiration: after a hour
  gc := gcache.New(10).
    LRU().
    Expiration(time.Hour).
    Build()
}

3 ref

GitHub - bluele/gcache: An in-memory cache library for golang. It supports multiple eviction policies: LRU, LFU, ARC