backup

.gitignore

@@ -0,0 +1,4 @@
+# Default ignored files
+/shelf/
+/.idea/workspace.xml
+.idea

df/磁盘处理记录.md

@@ -33,5 +33,4 @@ dev/sda3   /media/shixiaohua/a44c8a7c-5b7a-4e2a-8810-5af0561c94ac   ext4   defau
 mount
 # 查看磁盘分区
 lsblk
-```
-
+```

数据库/mysql/线程占用.md

@@ -7,8 +7,16 @@ information_schema这张数据表保存了MySQL服务器所有数据库的信息
 3. `innodb_lock_waits` 锁等待的对应关系
 
 ```sql
+-- 查看当前连接数
+SHOW STATUS LIKE 'Threads_connected';
+-- 查看系统设置连接数
+SHOW VARIABLES LIKE 'max_connections';
+-- 查看那个表被锁住
+SHOW OPEN TABLES WHERE In_use > 0;
 -- 查看哪个事物占用锁
 select * from information_schema.innodb_trx;
+-- 杀死进程
+kill trx_mysql_thread_id;
 select trx_mysql_thread_id from information_schema.innodb_trx where trx_state ='LOCK WAIT ';
 -- 查看所有进程
 show full processlist;