Oracle RAC阻塞排查SQL脚本

 

该使用到的sql脚本是参考别人技术文档转接过来用于日常工作中使用到的记录下。

1，树形结构分级别显示会话之间的阻塞关系

set lines 200 pages 100
col tree for a30
col event for a40
select *
  from (select a.inst_id, a.sid, a.serial#,
               a.sql_id,
               a.event,
               a.status,
               connect_by_isleaf as isleaf,
               sys_connect_by_path(a.SID||’@’||a.inst_id, ‘ <- ‘) tree,
               level as tree_level
          from gv$session a
         start with a.blocking_session is not null
        connect by (a.sid||’@’||a.inst_id) = prior (a.blocking_session||’@’||a.blocking_instance))
 where isleaf = 1
 order by tree_level asc;

效果如下：

2，直接显示会话阻塞关系

SELECT DISTINCT  
          s1.username  
       || ‘@’  
       || s1.machine  
       || ‘ ( INST=’  
       || s1.inst_id  
       || ‘ SID=’  
       || s1.sid  
       || ‘ Serail#=’  
       || s1.serial#  
       || ‘ ) IS BLOCKING ‘  
       || s2.username  
       || ‘@’  
       || s2.machine  
       || ‘ ( INST=’  
       || s2.inst_id  
       || ‘ SID=’  
       || s2.sid  
       || ‘ Serial#=’  
       || s2.serial#  
       || ‘ ) ‘  
          AS blocking_status  
  FROM gv$lock l1,  
       gv$session s1,  
       gv$lock l2,  
       gv$session s2  
 WHERE     s1.sid = l1.sid  
       AND s2.sid = l2.sid  
       AND s1.inst_id = l1.inst_id  
       AND s2.inst_id = l2.inst_id  
       AND l1.block > 0  
       AND l2.request > 0  
       AND l1.id1 = l2.id1  
       AND l1.id2 = l2.id2;

效果如下：

3，显示阻塞实例的sql语句（需要在RAC的每个实例上面去执行）

select b.sid,
       a.sql_id,
       a.sql_text,
       a.hash_value,
       b.username,
       b.machine,
       a.module,
       decode(c.block, 1, ‘blocking’) blocking,
       decode(c.request, 0, ‘null’, ‘blocked’) blocked,
       to_char(b.logon_time, ‘yyyy-mm-dd hh24:mi:ss’)
  from v$sql a, v$session b, v$lock c
 where c.type = ‘TX’
   and a.sql_id = b.sql_id
   and b.sid = c.sid
union all
select b.sid,
       a.sql_id,
       a.sql_text,
       a.hash_value,
       b.username,
       b.machine,
       a.module,
       decode(c.block, 1, ‘blocking’) blocking,
       decode(c.request, 0, ‘null’, ‘blocked’) blocked,
       to_char(b.logon_time, ‘yyyy-mm-dd hh24:mi:ss’)
  from v$sql a, v$session b, v$lock c
 where c.type = ‘TX’
   and a.sql_id = b.prev_sql_id
   and b.sid = c.sid
   and c.block = 1；

效果如下：