如何优化PHP开发中的缓存策略和算法

class LRUCache {
    private $capacity;
    private $cache;

    public function __construct($capacity) {
        $this->capacity = $capacity;
        $this->cache = [];
    }

    public function get($key) {
        if (isset($this->cache[$key])) {
            $value = $this->cache[$key];
            unset($this->cache[$key]);
            $this->cache[$key] = $value;
            return $value;
        } else {
            return -1;
        }
    }

    public function put($key, $value) {
        if (isset($this->cache[$key])) {
            unset($this->cache[$key]);
        } else {
            if (count($this->cache) >= $this->capacity) {
                array_shift($this->cache);
            }
        }
        $this->cache[$key] = $value;
    }
}

class DynamicCache {
    private $cache;
    private $expiration;

    public function __construct() {
        $this->cache = [];
        $this->expiration = [];
    }

    public function get($key) {
        if (isset($this->cache[$key]) && time() < $this->expiration[$key]) {
            return $this->cache[$key];
        } else {
            return null;
        }
    }

    public function put($key, $value, $expiration) {
        $this->cache[$key] = $value;
        $this->expiration[$key] = time() + $expiration;
    }
}

class MultiLevelCache {
    private $redis;
    private $fileCache;

    public function __construct() {
        $this->redis = new Redis();
        $this->redis->connect('127.0.0.1', 6379);

        $this->fileCache = new FileCache();
    }

    public function get($key) {
        $value = $this->redis->get($key);
        if ($value === false) {
            $value = $this->fileCache->get($key);
            if ($value !== null) {
                $this->redis->set($key, $value);
                $this->redis->expire($key, 3600);
            }
        }
        return $value;
    }

    public function put($key, $value) {
        $this->redis->set($key, $value);
        $this->redis->expire($key, 3600);
        
        $this->fileCache->put($key, $value);
    }
}