Bruce Momjian POSTGRESQL is an object-relational database developed on the Internet by a group of developers spread across the globe. It is an open-source alternative to commercial databases like Oracle and Informix. POSTGRESQL was originally develop…

http://msdn.microsoft.com/en-us/library/windows/hardware/jj248719.aspx This guide describes important tuning parameters and settings that you can adjust to improve the performance and energy efficiency of the Windows Server 2012 operating system. It…

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…

With MySQL, common configuration mistakes can cause serious performance problems. In fact, if you mis-configure just one of the many config parameters, it can cripple performance! (see examples) Of course, the performance of MySQL is often tied great…

本文译自Wikipedia的Performance tuning词条,原词条中的不少链接和扩展内容非常值得一读,翻译过程中暴露了个人工程学思想和英语水平的不足,翻译后的内容也失去很多准确性和丰富性,需要在之后的时间继续细读. Performance Tuning特指计算机系统的性能优化工作.它通常是根据某个现实或潜在的性能问题而发起的.绝大部分系统都会因为负载的升高而导致性能下降,一个系统对于负载的可承受能力称为可扩展性(scalability),调整系统使其可以承受更大的负载就是perform…

Spark SQL 之 Performance Tuning & Distributed SQL Engine 转载请注明出处:http://www.cnblogs.com/BYRans/ 缓存数据至内存(Caching Data In Memory) Spark SQL可以通过调用sqlContext.cacheTable("tableName") 或者dataFrame.cache(),将表用一种柱状格式( an in­memory columnar format)缓存至内…

IBM HTTP Server Performance Tuninghttp://publib.boulder.ibm.com/httpserv/ihsdiag/ihs_performance.html…

转自:http://www.cnblogs.com/WizardWu/archive/2008/10/27/1320055.html 有些程序员在撰写数据库应用程序时,常专注于 OOP 及各种 framework 的使用,却忽略了基本的 SQL 语句及其「性能 (performance) 优化」问题.版工曾听过台湾某半导体大厂的新进程序员,所组出来的一段 PL/SQL 跑了好几分钟还跑不完:想当然尔,即使他的 AJAX 及 ooxx 框架用得再漂亮,系统性能也会让使用者无法忍受.以下是版工整理出…

CSDN 对格式支持比較弱,能够到http://user.qzone.qq.com/88285879/blog/1399382878 看一致的内容. 前言Preface 包含例如以下几个小节 l Audience l Documentation Accessibility l Related Documents l Conventions 目标人群Audience Oracle Database Performance Tuning Guide 针对的人群是DBA.这个指南描写叙述了如何使用命O…

CSDN 对格式支持比較弱.能够到http://user.qzone.qq.com/88285879/blog/1399382878 看一致的内容. Performance Tuning Guide 11G中新增特性 本章描写叙述了Oracle11g Release2(11.2)中添加了哪些新的性能调整 特性,以及指向这些添加信息. 本章节描写叙述的特性以及增强,包括了优化数据库性能的各个方面. 关于Oracle11gR2的全部新特性汇总,能够查看Oracle Database New Feat…

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…

1.2性能调优特性和工具 Effective data collection and analysis isessential for identifying and correcting performance problems. Oracle providesa number of tools that allow a performance engineer to gather informationregarding database performance. In addition t…

Apache HBase Performance Tuning RAM, RAM, RAM. 不要让HBase饿死. 请使用64位的平台 必须将swapping设定为0 使用本地硬件来完成hdfs的checksumming计算,见:https://blogs.apache.org/hbase/entry/saving_cpu_using_native_hadoop 老年代使用CMS垃圾算法,设置-XX:CMSInitiatingOccupancyFraction为60或者70(越小代表发生越多G…

永无止境的调优 service level agreements: 是一个量化的调优的指标. performance 只要满足业务OK就可以了, 没必要调的很多, 因为有得必有失, 一方面调的特别优化, 可能导致另一方面出问题 主要还是关注SQL调优把(Troubleshooting Oracle performance 这本书主要是针对SQL的调优) 调优是告诉你怎么样使用ORACLE 没有1本书能大而全的论述性能调优 database administrators 和 system admi…

http://java.dzone.com/articles/performance-tuning For most typical Spring/Hibernate enterprise applications, the application performance depends almost entirely on the performance of it's persistence layer. This post will go over how to confirm that…

1 compress & mr hive默认的execution engine是mr hive> set hive.execution.engine;hive.execution.engine=mr 所以针对mr的优化就是hive的优化,比如压缩和临时目录 mapred-site.xml <property> <name>mapreduce.map.output.compress</name> <value>true</value>…

众所周知,glusterfs对小文件而言,就是个鸡肋,特别是在一个目录下有过W的小文件图片时,ls简单就是个坑,下面我对线上的glusterfs参数做一些优化调整,调整的命令: gluster volume set VOLNAME OPTION PARAMETER 参数如下: cluster.data-self-heal-algorithm ( full/diff ) cluster.min-free-disk ( Required minimum free disk space as a pe…

5 QUERY TUNING 5.1 Planner Method Configuration. 下列参数控制查询优化器是否使用特定的存取方法.除非对优化器特别了解,一般情况下,使用它们默认值即可. 5.1.1 enable_bitmapscan 布尔型 默认: enable_bitmapscan = on 打开或者关闭规划器对位图扫描规划类型的使用. 5.1.2 enable_hashagg 布尔型 默认: enable_hashagg = on 打开或者关闭查询规划器对散列连接规划类型的使用…

[root@bigdata-server-02 /]# ps --help all Usage: ps [options] Basic options: -A, -e all processes -a all with tty, except session leaders a all with tty, including other users -d all except session leaders -N, --deselect negate selection r only runni…

一.Creating a trace or workload 注意点: In the Trace Properties dialog box, there is a checkbox option in the General tab with the caption Server processes trace data, to specify whethertrace data should be processed on the server. If not checked, trace…

最近重装了windows8系统,发现性能差得很,远不如官方说的比win7好很多的说法.经过几个关键配置的调整,终于找回电脑原来的风采. 下面总结一下,希望对大家有帮助: 1. 检查windows服务,把不需要的服务关闭.键盘windows+R后输入services.msc再按回车,这个时候会弹出电脑服务管理窗口. 其中最容易被遗忘的时windows media network service,不需要网络多媒体共享的朋友最好关掉它,它扫描媒体可是很吃硬盘的. 2. 看一下电源选项(电脑右下角有个电…

1.表级锁状态 mysql> show status like 'table%'; +----------------------------+-----------+ | Variable_name              | Value     | +----------------------------+-----------+ | Table_locks_immediate      | 139306577 |     | Table_locks_waited         | 0…

My colleague suddenly encountered a problem today,a Database becomes very slow , and the a lot of session wait library cache lock event, Let me help him to look. DB env is 10.2.0.4 rac. at first ,to generate a AWR manually. exec dbms_workload_reposit…

通常来说,MySQL性能调优是非常复杂的一件事,不是简单的修改参数就可以完成的.需要综合考虑.而且找出性能瓶颈也非易事.但是通常我们有以下的几种方法找到蛛丝马迹.通过下面的几种方法发现瓶颈以后,我们才能确定下一步应该怎么做^_^ 其他的可以参考我前面写的文章:MySQL常用SQL优化,Linux上跑MySQL优化 (1)查看系统状态,比如top,vmstat,sar,iostat,dstat等(2)进入MySQL里查看MySQL的连接数及相应的SQL(show processlist)(3)如果…

Creating trace with system stored procedures Following are the stored procedures which you should know: sp_trace_create: This stored procedure is used to create a trace and returns the ID of newly created trace sp_trace_setevent: This stored procedur…

PostgreSQL相关的软件,库,工具和资源集合. 备份 wal-e - Simple Continuous Archiving for Postgres to S3, Azure, or Swift by Heroku Barman - Backup and Recovery Manager for Postgres by 2ndQuadrant GUI pgAdmin - Postgres Administration and Management GUI phpPgAdmin - The…

https://github.com/ty4z2008/Qix/blob/master/pg.md?from=timeline&isappinstalled=0 PostgreSQL(数据库)资料 About:PostgreSQL About <PostgreSQL 源码分析系列> PostgreSQL 源码分析系列 介绍:PostgreSQL 源码分析系列文章 <PG 内存上下文> 介绍:PG 内存上下文,code <PostgreSQL及其代码的结构> 介绍…

Microservices What are Microservices? What are Microservices - microservices.io Microservices - martinFowler.com What is Microservices? - SmartBear What are Microservices? - RedHat The What, Why, and How of a Microservices Architecture What are Micro…

http://queue.acm.org/detail.cfm?id=1854041 The July/August issue of acmqueue is out now acmqueue is free for ACM professional members. Non-members can purchase an annual subscription for $19.99 or a single issue for $6.99. Download the app from iTune…

Java Performance Optimization by: Pierre-Hugues Charbonneau reference:http://refcardz.dzone.com/refcardz/java-performance-optimization Java is among the most widely used programming languages in the software development world today. Java applications…