修改错误单词&简化代码

redis/pessimistic-lock.php

@@ -0,0 +1,38 @@
+<?php
+/**
+ * redis实战
+ *
+ * 实现悲观锁机制
+ *
+ * @author TIGERB <https://github.com/TIGERB>
+ * @example php pessimistic-lock.php
+ */
+
+$redis = new \Redis();
+$redis->connect('127.0.0.1', 6379);
+
+$timeout = 3;
+$lockKey = 'lock.count';
+do {
+    // 上锁
+    $isLock = $redis->set($lockKey, '1', ['nx', 'ex' => $timeout]); // 避免死锁，设置 $timeout
+    if (!$isLock) {
+        // 睡眠 降低抢锁频率　缓解redis压力
+        echo "资源繁忙，正在重试...". microtime(true) . PHP_EOL;
+        usleep(5000);
+    } else {
+        break;
+    }
+} while (!$isLock);
+
+$key = 'count';
+// 执行业务逻辑
+echo "执行count加1操作～" . PHP_EOL;
+$redis->incr($key);
+
+// 删除锁
+$redis->del($lockKey);
+
+// 打印 count 值
+$count = $redis->get($key);
+echo "count值为：{$count} " . PHP_EOL;