dw-cache

Dual Window Cache

Dual window cache adaptively coordinates the ratio of LRU to LFU using the two sliding windows.

Maintenance

This repository is maintained on the following source repository.

https://github.com/falsandtru/spica

Performance comparison

Hit rate

Higher x1.0-2.7 hit rate of LRU.

'Cache even 100'
'LRU hit rate', 9.87
'DWC hit rate', 9.84
'DWC ratio', 0, 0
'DWC / LRU hit rate ratio', '99%'

'Cache uneven 100'
'LRU hit rate', 19.14
'DWC hit rate', 36.52
'DWC ratio', 95, 93
'DWC / LRU hit rate ratio', '190%'

'Cache uneven 100 transitive distribution'
'LRU hit rate', 17.74
'DWC hit rate', 37.15
'DWC ratio', 95, 95
'DWC / LRU hit rate ratio', '209%'

'Cache uneven 100 transitive bias'
'LRU hit rate', 10.99
'DWC hit rate', 11.02
'DWC ratio', 0, 1
'DWC / LRU hit rate ratio', '100%'

'Cache uneven 100 sequential'
'LRU hit rate', 13.47
'DWC hit rate', 37.53
'DWC ratio', 95, 95
'DWC / LRU hit rate ratio', '278%'

'Cache uneven 100 adversarial'
'LRU hit rate', 41.78
'DWC hit rate', 49.77
'DWC ratio', 94, 93
'DWC / LRU hit rate ratio', '119%'

https://github.com/falsandtru/spica/runs/4998610954

Benchmark

±10% speed of lru-cache.

'LRUCache simulation 100 x 4,248,360 ops/sec ±0.96% (64 runs sampled)'

'DW-Cache simulation 100 x 3,814,501 ops/sec ±0.71% (63 runs sampled)'

'LRUCache simulation 1,000 x 3,160,547 ops/sec ±6.42% (51 runs sampled)'

'DW-Cache simulation 1,000 x 3,945,506 ops/sec ±1.11% (61 runs sampled)'

'LRUCache simulation 10,000 x 2,485,636 ops/sec ±2.86% (57 runs sampled)'

'DW-Cache simulation 10,000 x 2,585,085 ops/sec ±3.09% (61 runs sampled)'

'LRUCache simulation 100,000 x 1,334,175 ops/sec ±3.50% (56 runs sampled)'

'DW-Cache simulation 100,000 x 1,317,095 ops/sec ±6.04% (54 runs sampled)'

'LRUCache simulation 1,000,000 x 837,846 ops/sec ±6.75% (55 runs sampled)'

'DW-Cache simulation 1,000,000 x 726,036 ops/sec ±8.35% (56 runs sampled)'

https://github.com/falsandtru/spica/runs/4998624993

API

export class Cache<K, V = undefined> {
  constructor(capacity: number, opts?: Cache.Options<K, V>);
  constructor(opts: Cache.Options<K, V>);
  put(key: K, value: V, size?: number, age?: number): boolean;
  set(key: K, value: V, size?: number, age?: number): this;
  get(key: K): V | undefined;
  has(key: K): boolean;
  delete(key: K): boolean;
  clear(): void;
  readonly length: number;
  readonly size: number;
  [Symbol.iterator](): Iterator<[K, V], undefined, undefined>;
}
namespace Cache {
  export interface Options<K, V = undefined> {
    readonly space?: number;
    readonly age?: number;
    readonly life?: number;
    readonly limit?: number;
    readonly disposer?: (value: V, key: K) => void;
    readonly capture?: {
      readonly delete?: boolean;
      readonly clear?: boolean;
    };
  }
}