Redis缓存的LRU淘汰策略配置的实现

# redis.conf
# 设置最大内存为256MB
maxmemory 256mb

redis-server --maxmemory 256mb

# redis.conf
# 设置淘汰策略为所有键使用LRU算法
maxmemory-policy allkeys-lru

redis-server --maxmemory 256mb --maxmemory-policy allkeys-lru

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

public class RedisLRUExample {

    public static void main(String[] args) {
        // 配置Jedis连接池
        JedisPoolConfig poolConfig = new JedisPoolConfig();
        poolConfig.setMaxTotal(10);
        JedisPool jedisPool = new JedisPool(poolConfig, "localhost", 6379);

        try (Jedis jedis = jedisPool.getResource()) {
            // 配置Redis最大内存和淘汰策略
            jedis.configSet("maxmemory", "256mb");
            jedis.configSet("maxmemory-policy", "allkeys-lru");

            // 检查配置是否生效
            System.out.println("Maxmemory: " + jedis.configGet("maxmemory"));
            System.out.println("Maxmemory-policy: " + jedis.configGet("maxmemory-policy"));

            // 添加一些键值对
            for (int i = 1; i <= 100; i++) {
                jedis.set("key" + i, "value" + i);
            }

            // 模拟访问一些键
            for (int i = 1; i <= 50; i++) {
                jedis.get("key" + i);
            }

            // 添加更多键值对以触发LRU淘汰
            for (int i = 101; i <= 150; i++) {
                jedis.set("key" + i, "value" + i);
            }

            // 检查哪些键仍然存在
            for (int i = 1; i <= 150; i++) {
                if (jedis.exists("key" + i)) {
                    System.out.println("Key exists: key" + i);
                }
            }
        }

        jedisPool.close();
    }
}

import redis.clients.jedis.Jedis;

public class RedisInfoExample {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("localhost", 6379);

        // 获取Redis信息
        String info = jedis.info("memory");
        System.out.println(info);

        jedis.close();
    }
}

import redis.clients.jedis.Jedis;

public class RedisMonitoringExample {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("localhost", 6379);

        // 获取Redis的内存使用信息
        String memoryInfo = jedis.info("memory");
        System.out.println(memoryInfo);

        // 获取Redis的命中率信息
        String statsInfo = jedis.info("stats");
        System.out.println(statsInfo);

        jedis.close();
    }
}