标签归档:resmgr:cpu quantum

resmgr:cpu quantum等待

昨天晚上数据库升级(使用exp/imp从9i升级到11g),开启业务,数据库出现很多resmgr:cpu quantum等待

SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for IBM/AIX RISC System/6000: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

SQL> SELECT sid,event FROM v$session WHERE wait_class#<>6;

       SID EVENT
---------- ----------------------------------------------------------------
        27 resmgr:cpu quantum
        38 resmgr:cpu quantum
        43 resmgr:cpu quantum
        46 resmgr:cpu quantum
       113 resmgr:cpu quantum
       118 resmgr:cpu quantum
       125 resmgr:cpu quantum
       140 resmgr:cpu quantum
       143 resmgr:cpu quantum
       199 resmgr:cpu quantum
       205 resmgr:cpu quantum

       SID EVENT
---------- ----------------------------------------------------------------
       212 resmgr:cpu quantum
       220 resmgr:cpu quantum
       221 resmgr:cpu quantum
       223 resmgr:cpu quantum
       238 resmgr:cpu quantum
       241 resmgr:cpu quantum
       301 resmgr:cpu quantum
       313 resmgr:cpu quantum
       314 resmgr:cpu quantum
       405 resmgr:cpu quantum
       410 resmgr:cpu quantum

       SID EVENT
---------- ----------------------------------------------------------------
       415 resmgr:cpu quantum
       435 resmgr:cpu quantum
       502 resmgr:cpu quantum
       503 resmgr:cpu quantum
       509 resmgr:cpu quantum
       510 resmgr:cpu quantum
       512 resmgr:cpu quantum
       521 resmgr:cpu quantum
       526 resmgr:cpu quantum
       528 resmgr:cpu quantum
       532 resmgr:cpu quantum

       SID EVENT
---------- ----------------------------------------------------------------
       533 enq: TX - row lock contention
       589 resmgr:cpu quantum
       596 resmgr:cpu quantum
       600 resmgr:cpu quantum
       609 resmgr:cpu quantum
       611 resmgr:cpu quantum
       625 resmgr:cpu quantum
       635 null event
       707 resmgr:cpu quantum
       727 resmgr:cpu quantum
       731 SQL*Net message to client

44 rows selected.

查询alert日志

Sat Jun 09 06:00:00 2012
Setting Resource Manager plan SCHEDULER[0x310C]:DEFAULT_MAINTENANCE_PLAN via scheduler window
Setting Resource Manager plan DEFAULT_MAINTENANCE_PLAN via parameter
Sun Jun 10 02:00:00 2012
Closing Resource Manager plan via scheduler window
Clearing Resource Manager plan via parameter

Sun Jun 10 06:00:00 2012
Setting Resource Manager plan DEFAULT_MAINTENANCE_PLAN via parameter
Mon Jun 11 02:00:00 2012
Closing Resource Manager plan via scheduler window
Clearing Resource Manager plan via parameter

Mon Jun 11 22:00:00 2012
Setting Resource Manager plan DEFAULT_MAINTENANCE_PLAN via parameter
Tue Jun 12 02:00:00 2012
Closing scheduler window
Closing Resource Manager plan via scheduler window
Clearing Resource Manager plan via parameter

Tue Jun 12 22:00:00 2012
Setting Resource Manager plan SCHEDULER[0x3108]:DEFAULT_MAINTENANCE_PLAN via scheduler window
Setting Resource Manager plan DEFAULT_MAINTENANCE_PLAN via parameter
Wed Jun 13 02:00:00 2012
Closing scheduler window
Closing Resource Manager plan via scheduler window
Clearing Resource Manager plan via parameter

从这里可以看出来,因为SCHEDULER定时启动和关闭资源管理的DEFAULT_MAINTENANCE_PLAN从而导致在晚上10点到2点Resource Manager plan处于启用状态.上线测试刚好在晚上2点之前,所有当时查询的时候发现很多resmgr:cpu quantum等待是因为Resource Manager plan启用导致(使用SCHEDULER控制其启用和关闭),很多情况下数据库跑的应用比较单一,不是十分的需要启动资源管理.
在11g中关闭方法如下

1. Set the current resource manager plan to null (or another plan that is not restrictive):

alter system set resource_manager_plan='' scope=both;

2. Change the active windows to use the null resource manager plan (or other nonrestrictive plan) using:

execute dbms_scheduler.set_attribute('WEEKNIGHT_WINDOW','RESOURCE_PLAN',''); 
execute dbms_scheduler.set_attribute('WEEKEND_WINDOW','RESOURCE_PLAN','');

3. Then, for each window_name (WINDOW_NAME from DBA_SCHEDULER_WINDOWS), run:

execute dbms_scheduler.set_attribute('<window name>','RESOURCE_PLAN','');

SQL> select WINDOW_NAME  from DBA_SCHEDULER_WINDOWS;

WINDOW_NAME
------------------------------
MONDAY_WINDOW
TUESDAY_WINDOW
WEDNESDAY_WINDOW
THURSDAY_WINDOW
FRIDAY_WINDOW
SATURDAY_WINDOW
SUNDAY_WINDOW
WEEKNIGHT_WINDOW
WEEKEND_WINDOW

9 rows selected.
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