EhCache、GuavaCache和Caffeine之间的性能比较

使用JMH实际测试EhCache、GuavaCache和Caffeine之间的性能

测试代码

EhCache

@BenchmarkMode({Mode.AverageTime})
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations=3, time = 5, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations=5,time = 1,timeUnit = TimeUnit.SECONDS)
@Threads(8)
@Fork(3)
@State(Scope.Thread)
public class EhCacheTest {
    private static CacheManager cacheManager = CacheManagerBuilder.newCacheManagerBuilder()
            .build(true);

    private static Cache<String, String> cache = cacheManager.createCache("myCache",
            CacheConfigurationBuilder.newCacheConfigurationBuilder(String.class, String.class,
                    ResourcePoolsBuilder.newResourcePoolsBuilder().heap(100, MemoryUnit.MB))
                    .withExpiry(ExpiryPolicyBuilder.timeToLiveExpiration(Duration.ofSeconds(1L))).build());

    static {
        cache.put("test","test");
    }
    @Benchmark
    public void test(){
        cache.get("test");
    }
}

Guava Cache


@BenchmarkMode({Mode.AverageTime})
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations=3, time = 5, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations=5,time = 1,timeUnit = TimeUnit.SECONDS)
@Threads(8)
@Fork(3)
@State(Scope.Thread)
public class GuavaTest {
    private static Cache<String,String> cache = CacheBuilder.newBuilder()
            .maximumSize(100)
            .expireAfterWrite(1,TimeUnit.SECONDS)
            .build();

    static {
        cache.put("test","test");
    }

    @Benchmark
    public void test(){
        cache.getIfPresent("test");
    }
}

Caffeine


@BenchmarkMode({Mode.AverageTime})
@OutputTimeUnit(TimeUnit.MICROSECONDS)
@Warmup(iterations=3, time = 5, timeUnit = TimeUnit.MILLISECONDS)
@Measurement(iterations=5,time = 1,timeUnit = TimeUnit.SECONDS)
@Threads(8)
@Fork(3)
@State(Scope.Thread)
public class CaffeineTest {
    private static Cache<String,String> cache = Caffeine.newBuilder()
            .maximumSize(100)
            .expireAfterWrite(1,TimeUnit.SECONDS)
            .build();

    static {
        cache.put("test","test");
    }

    @Benchmark
    public void test(){
        cache.getIfPresent("test");
    }
}

说明，实际测试代码共有六种情况（其实还有别的情况，不加任何参数使Caffeine使用UnboundedLocalCache，性能应该还会改变，大家如果有兴趣可以自己尝试）

直接放结果

• 奇特的地方
  • 在加过期时间的情况下三个缓存方案的性能均有所提升
  • Guava不加过期时间的情况下高并发会OOM
  • EhCache在加过期时间的情况下竟然比Guava的性能要好
  • Caffeine读比写的性能要高很多

总结

• Guava使用jdk的Queue记录缓存的写读情况，导致OOM；而Caffeine使用Disruptor的RingBuffer数据结构记录
• Caffeine对写的所有线程共用一个RingBuffer；而对读的每个线程维护一个RingBuffer
• 使用Caffeine是你不会后悔的选择
• 可参考Caffeine