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A multiprocessing system having a plurality of processing nodes interconnected by an interconnect network. To optimize performance during spin-lock operations, a home agent prioritizes the servicing of read-to-own (RTO) transaction requests over the…
MySQL performance tuning primer script一个简单好用的mysql优化工具,其实一个shell脚本 下载: $ wget http://www.day32.com/MySQL/tuning-primer.sh 运行 $ sh tuning-primer.sh all 运行以后会询问mysql用户名好密码最好提供mysql的,还会询问是否在当家目录自动生成.my.cnf配置文件这里保存你的mysql用户名和密码一般选择N. 它主要通过查询mysql中的variab…
APPLIES TO: Oracle Database - Enterprise Edition - Version 8.1.7.4 to 11.2.0.1 [Release 8.1.7 to 11.2]Information in this document applies to any platform.***Checked for relevance on 03-Nov-2014*** PURPOSE This article describes what happens when a s…
排序合并连接 (Sort Merge Join)是一种两个表在做连接时用排序操作(Sort)和合并操作(Merge)来得到连接结果集的连接方法. 对于排序合并连接的优缺点及适用场景例如以下: a,通常情况下.排序合并连接的运行效率远不如哈希连接,但前者的使用范围更广.由于哈希连接仅仅能用于等值连接条件,而排序合并连接还能用于其它连接条件(如<,<=,>.>=) b,通常情况下.排序合并连接并不适合OLTP类型的系统.其本质原因是对于由于OLTP类型系统而言,排序是很昂贵的操作,当然…
老李分享: Oracle Performance Tuning Overview 翻译   poptest是国内唯一一家培养测试开发工程师的培训机构,以学员能胜任自动化测试,性能测试,测试工具开发等工作为目标.如果对课程感兴趣,请大家咨询qq:908821478,咨询电话010-84505200. 1 性能优化概述 This chapter provides an introduction toperformance tuning and contains the following secti…
QUESTION 13 View the Exhibit.Examine the following command that is executed for the TRANSPORT table in the SH schema:SQL> SELECT DBMS_STATS.CREATE_EXTENDED_STATS('sh', 'customers_obe', '(country_id,cust_state_province)') FROM dual;Which statement des…
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[root@server-mysql mytop-1.6]# wget http://www.day32.com/MySQL/tuning-primer.sh --2016-07-03 19:42:33-- http://www.day32.com/MySQL/tuning-primer.sh Resolving www.day32.com... 192.237.221.190 Connecting ... connected. HTTP request sent, awaiting respo…