老李分享： Oracle Performance Tuning Overview 翻译下

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 to gathering data, Oracle providestools to monitor performance, diagnose problems, and tune applications.

有效数据的收集分析对找出并改正性能问题是很必要的。就数据库的性能，oracle提供了大量的工具，这些工具允许性能调优工程师收集信息.除了收集数据，oracle提供了一些工具来监测性能，诊断问题和调优应用程序。

The Oracle gathering and monitoring featuresare mainly automatic, managed by an Oracle background processes. To enableautomatic statistics collection and automatic performance features,the STATISTICS_LEVEL initialization parameter must be setto TYPICAL or ALL. You can administer and display the output ofthe gathering and tuning tools with Oracle Enterprise Manager, or with APIs andviews. For ease of use and to take advantage of its numerous automated monitoringand diagnostic tools, Oracle Enterprise Manager Database Control isrecommended.

oracle收集和监控特性主要都是自动的，被oracle后台进程管理。为了使统计收集和性能功能自动化，统计级别这个初始化参数必须被设置为典型或完全。你可以用oracle企业管理器或者API或者视图来展示和管理统计信息收集和调优工具的输出结果。为了更加方便的使用和利用大量的自动监测诊断工具，推荐使用oracle企业管理器数据库控制。

1.2.1自动性能调优特性

The Oracle automatic performance tuningfeatures include:

oracle 自动性能调优特性包括以下

Automatic Workload Repository (AWR) collects, processes, and maintains performance statistics for problem detection and self-tuning purposes. See "Overview of the Automatic Workload Repository".
自动工作信息库收集，加工和维护性能统计信息来检测问题和自我优化。详见自动负载信息库概论。
Automatic Database Diagnostic Monitor (ADDM) analyzes the information collected by the AWR for possible performance problems with the Oracle database. See "Automatic Database Diagnostic Monitor".
自动数据库诊断和监测工具针对oracle数据库可能的性能问题分析了AWR收集的信息。详见自动数据库诊断监控。
SQL Tuning Advisor allows a quick and efficient technique for optimizing SQL statements without modifying any statements. See "SQL Tuning Advisor".
sql优化建议器提供了不修改sql语句的一个快速有效的sql优化技术。详见 sql优化建议器。
SQLAccess Advisor provides advice on materialized views, indexes, and materialized view logs. See "Automatic SQL Tuning Features" and "Overview of the SQL Access Advisor in the DBMS_ADVISOR Package" for information on SQLAccess Advisor.
sql访问建议器提供了在物化视图，索引，物化视图日志上的一些建议。请阅读自动sql优化特性和数据库建议包里的sql访问建议器概述。
End to End Application tracing identifies excessive workloads on the system by specific user, service, or application component. See "End to End Application Tracing".
端到端的应用程序追踪器能够通过特殊用户服务和应用程序组件来标识出系统上过度负载的地方。详见端到端程序追踪。
Server-generated alerts automatically provide notifications when impending problems are detected. See Oracle Database Administrator's Guide for information about monitoring the operation of the database with server-generated alerts.
当问题逼近的时候，服务器产生的告警日志会自动通知。关于用服务器告警日志监控数据运行的更多信息详见“oracle数据库管理员指南”。
Additional advisors that can be launched from Oracle Enterprise Manager, such as memory advisors to optimize memory for an instance. The memory advisors are commonly used when automatic memory management is not set up for the database. Other advisors are used to optimize mean time to recovery (MTTR), shrinking of segments, and undo tablespace settings. For information about using advisors that are available with Oracle Enterprise Manager, see Oracle Database 2 Day + Performance Tuning Guide.
oracle企业级管理器能够提供额外的建议参考信息，例如内存建议为实例优化内存。当没有为数据库设置自动内存管理的时候，内存建议器通常被使用。另外一些建议器被用来优化恢复的平均耗时时间和段的收缩和回滚段空间设置。若要关于使用oracle企业管理器顾问的更多信息，请阅读”两天掌握oracle+性能调优指南”。
The Database Performance page in Oracle Enterprise Manager displays host, instance service time, and throughput information for real time monitoring and diagnosis. The page can be set to refresh automatically in selected intervals or manually. For information about the Database Performance page, see Oracle Database 2 Day + Performance Tuning Guide.
数据库企业管理器里的数据库性能笔记显示了主机实例服务时间、实时的诊断信息和吞吐量。这个笔记能够在选定的时间段内自动刷新或者人工刷新。关于性能调优笔记的更多信息请阅读”2天掌握oracle数据库+数据库调优指南”。

1.2.2额外的数据库工具

This section describes additional Oracletools that can be used for determining performance problems.

这部分描述了能够被用来确定oracle性能问题的额外工具.

1.2.2.1 V$开头的性能视图

The V$ views are the performanceinformation sources used by all Oracle performance tuning tools.The V$ views are based on memory structures initialized at instancestartup. The memory structures, and the views that represent them, areautomatically maintained by Oracle throughout the life of the instance.See Chapter 10, "Instance Tuning Using PerformanceViews" for information diagnosing tuning problems usingthe V$ performance views.

V$视图是所有的oracle性能调优工具使用的性能信息的源头。V$视图基于实例启动时被初始化的内存结构。内存结构和代表他们的视图在实例的整个生命周期会被oracle自动维护。请阅读 10章节“使用性能视图的实例优化”来获取使用V$性能视图来诊断调优问题的更多信息。