Redis过期性能提升之多线程优化（redis过期 多线程）
Redis过期性能提升之多线程优化
Redis是一种存储和访问数据的高性能缓存系统，其过期机制是被广泛使用的功能之一。但是随着数据量的增加，Redis过期机制在高并发情况下的性能瓶颈逐渐显现。在多线程的帮助下，可以优化Redis的过期机制，提升其高并发场景下的性能表现。
多线程的实现方式有很多，这里介绍一种基于Java的多线程过期实现方案。我们需要利用Redis中的Keyspace Notifications功能，实现对Redis缓存过期事件的监听。Java代码如下：
“`java
public class RedisKeyExpireListener extends JedisPubSub {
private ThreadLocal jedisPoolThreadLocal = new ThreadLocal();
private BlockingQueue cacheObjectEventQueue = new LinkedBlockingQueue();
@Override
public void onPSubscribe(String pattern, int subscribedChannels) {
// 订阅成功回调
}
@Override
public void onPMessage(String pattern, String channel, String message) {
String[] messageArr = message.split(“:”);
String cacheKey = messageArr[0];
String expired = messageArr[1];
Jedis jedis = jedisPoolThreadLocal.get().getResource();
if (expired.equals(“expired”)) {
cacheObjectEventQueue.offer(new CacheObjectEvent(cacheKey, jedis));
}
}
public static void mn(String[] args) {
JedisPool jedisPool = new JedisPool(“localhost”, 6379);
jedisPool.getResource().psubscribe(new RedisKeyExpireListener(), “__keyevent@0__:expired”);
}
}
上述代码中，我们首先继承了Redis的JedisPubSub类，实现了针对Redis的监听功能。在监听到Redis缓存数据过期时，我们将会触发缓存数据的事件，将其加入到阻塞队列中。当我们缓存数据需要进行处理时，可以从这个阻塞队列中取出事件进行处理。
接下来，我们需要实现一个缓存数据过期的处理类，该类可以利用多线程进行优化，提升系统的性能表现。Java代码如下：
```javapublic class CacheObjectEventThread implements Runnable {
private BlockingQueue cacheObjectEventQueue;
private ExecutorService executorService;
public CacheObjectEventThread(BlockingQueue cacheObjectEventQueue, int threadNum) {
this.cacheObjectEventQueue = cacheObjectEventQueue; this.executorService = Executors.newFixedThreadPool(threadNum);
}
@Override public void run() {
while (true) { CacheObjectEvent cacheObjectEvent = null;
try { cacheObjectEvent = cacheObjectEventQueue.take();
} catch (InterruptedException e) { e.printStackTrace();
} executorService.execute(() -> {
String cacheKey = cacheObjectEvent.getCacheKey(); Jedis jedis = cacheObjectEvent.getJedis();
jedis.del(cacheKey); jedis.close();
}); }
}
public static void mn(String[] args) { CacheObjectEventThread cacheObjectEventThread = new CacheObjectEventThread(new LinkedBlockingQueue(), 10);
new Thread(cacheObjectEventThread).start(); }
}
上述代码中，我们实现了一个基于Java的多线程缓存数据过期类，该类采用阻塞队列的方式存储监听事件，并且可以采用多线程的方式进行事件的处理。通过定义一个线程池，可以按需创建多个线程来处理事件，从而提高并行处理能力。
我们需要将两个类结合在一起，完整地实现基于Java的多线程Redis过期机制优化。Java代码如下：
“`java
public class RedisKeyExpireListener extends JedisPubSub {
private ThreadLocal jedisPoolThreadLocal = new ThreadLocal();
private BlockingQueue cacheObjectEventQueue = new LinkedBlockingQueue();
@Override
public void onPSubscribe(String pattern, int subscribedChannels) {
// 订阅成功回调
}
@Override
public void onPMessage(String pattern, String channel, String message) {
String[] messageArr = message.split(“:”);
String cacheKey = messageArr[0];
String expired = messageArr[1];
Jedis jedis = jedisPoolThreadLocal.get().getResource();
if (expired.equals(“expired”)) {
cacheObjectEventQueue.offer(new CacheObjectEvent(cacheKey, jedis));
}
}
public static void mn(String[] args) {
JedisPool jedisPool = new JedisPool(“localhost”, 6379);
jedisPool.getResource().psubscribe(new RedisKeyExpireListener(), “__keyevent@0__:expired”);
CacheObjectEventThread cacheObjectEventThread = new CacheObjectEventThread(new LinkedBlockingQueue(), 10);
new Thread(cacheObjectEventThread).start();
}
}
public class CacheObjectEvent {
private String cacheKey;
private Jedis jedis;
public CacheObjectEvent(String cacheKey, Jedis jedis) {
this.cacheKey = cacheKey;
this.jedis = jedis;
}
public String getCacheKey() {
return cacheKey;
}
public Jedis getJedis() {
return jedis;
}
}
public class CacheObjectEventThread implements Runnable {
private BlockingQueue cacheObjectEventQueue;
private ExecutorService executorService;
public CacheObjectEventThread(BlockingQueue cacheObjectEventQueue, int threadNum) {
this.cacheObjectEventQueue = cacheObjectEventQueue;
this.executorService = Executors.newFixedThreadPool(threadNum);
}
@Override
public void run() {
while (true) {
CacheObjectEvent cacheObjectEvent = null;
try {
cacheObjectEvent = cacheObjectEventQueue.take();
} catch (InterruptedException e) {
e.printStackTrace();
}
executorService.execute(() -> {
String cacheKey = cacheObjectEvent.getCacheKey();
Jedis jedis = cacheObjectEvent.getJedis();
jedis.del(cacheKey);
jedis.close();
});
}
}
public static void mn(String[] args) {
CacheObjectEventThread cacheObjectEventThread = new CacheObjectEventThread(new LinkedBlockingQueue(), 10);
new Thread(cacheObjectEventThread).start();
}
}
多线程在Redis过期处理中有很大的优势，可以通过优化系统的芯片性能，提高系统的处理性能。同时，在国内，通过多线程以及其他技术的优化，也可以实现高速的缓存系统，有效提高其竞争力。
