Oracle AWR SQL监控指标详细解释
一般情况我们作为非DBA人士,只关注一些SQL的指标,主要指标见下图, 详细的解释见下面的描述。 SQL ordered byElapsed Time 记
一般情况我们作为非DBA人士,只关注一些SQL的指标,主要指标见下图,,
详细的解释见下面的描述。
SQL ordered byElapsed Time
记录了执行总和时间的TOP SQL(请注意是监控范围内该SQL的执行时间总和,而不是单次SQL执行时间 Elapsed Time = CPU Time + Wait Time)。
Elapsed Time(S): SQL语句执行用总时长,此排序就是按照这个字段进行的。注意该时间不是单个SQL跑的时间,而是监控范围内SQL执行次数的总和时间。单位时间为秒。ElapsedTime = CPU Time + Wait Time
CPU Time(s): 为SQL语句执行时CPU占用时间总时长,此时间会小于等于Elapsed Time时间。单位时间为秒。
Executions: SQL语句在监控范围内的执行次数总计。
Elap per Exec(s): 执行一次SQL的平均时间。单位时间为秒。
% Total DB Time: 为SQL的Elapsed Time时间占数据库总时间的百分比。
SQL ID: SQL语句的ID编号,点击之后就能导航到下边的SQL详细列表中,点击IE的返回可以回到当前SQL ID的地方。
SQL Module: 显示该SQL是用什么方式连接到数据库执行的,如果是用SQL*Plus或者PL/SQL链接上来的那基本上都是有人在调试程序。一般用前台应用链接过来执行的sql该位置为空。
SQL Text: 简单的sql提示,详细的需要点击SQL ID。
}SQL ordered by CPUTime:
}记录了执行占CPU时间总和时间最长的TOP SQL(请注意是监控范围内该SQL的执行占CPU时间总和,而不是单次SQL执行时间)。
}SQL ordered by Gets:
}记录了执行占总buffer gets(逻辑IO)的TOP SQL(请注意是监控范围内该SQL的执行占Gets总和,而不是单次SQL执行所占的Gets)
Buffer Gets 获取buffer的总数。
Gets per Exec 执行一次获取buffer数。
%Total BufferGets/ Total Buffer Gets
}SQL ordered byReads:
}记录了执行占总磁盘物理读(物理IO)的TOP SQL(请注意是监控范围内该SQL的执行占磁盘物理读总和,而不是单次SQL执行所占的磁盘物理读)。
Physical Reads 读取磁盘总数。
Reads per Exec 平均一次执行读取的磁盘数。
%Total Physical Reads/Total Disk Reads
}SQL ordered byExecutions:
}记录了按照SQL的执行次数排序的TOP SQL。该排序可以看出监控范围内的SQL执行次数。
Rows Processed 结果总行数
Rows per Exec 平均每次结果行数
}SQL ordered by ParseCalls:
}记录了SQL的软解析次数的TOP SQL。说到软解析(soft prase)和硬解析(hard prase),就不能不说一下Oracle对sql的处理过程。
Parse Calls 该sql软解析总次数
% Total Parses 该sql占总的软解析次数的百分比
}SQL ordered bySharable Memory:
}记录了SQL占用library cache的大小的TOP SQL。Sharable Mem (b):占用library cache的大小,单位是byte,列出超过1048576byte。
Sharable Mem (b) 该sql占用的libCache的大小
% Total 占library cache 的百分比
}SQL ordered byVersion Count:
}记录了SQL的打开子游标的TOP SQL,列出打开子游标大于20。
Version Count 打开的子游标数
}SQL ordered byCluster Wait Time:
}记录了集群的等待时间的TOP SQL
Cluster Wait Time (s) 等待时间
CWT % of ElapsdTime 表示等待时间/总的执行时间的百分比

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

The article discusses using MySQL's ALTER TABLE statement to modify tables, including adding/dropping columns, renaming tables/columns, and changing column data types.

Article discusses configuring SSL/TLS encryption for MySQL, including certificate generation and verification. Main issue is using self-signed certificates' security implications.[Character count: 159]

Article discusses strategies for handling large datasets in MySQL, including partitioning, sharding, indexing, and query optimization.

Article discusses popular MySQL GUI tools like MySQL Workbench and phpMyAdmin, comparing their features and suitability for beginners and advanced users.[159 characters]

The article discusses dropping tables in MySQL using the DROP TABLE statement, emphasizing precautions and risks. It highlights that the action is irreversible without backups, detailing recovery methods and potential production environment hazards.

The article discusses creating indexes on JSON columns in various databases like PostgreSQL, MySQL, and MongoDB to enhance query performance. It explains the syntax and benefits of indexing specific JSON paths, and lists supported database systems.

Article discusses using foreign keys to represent relationships in databases, focusing on best practices, data integrity, and common pitfalls to avoid.

Article discusses securing MySQL against SQL injection and brute-force attacks using prepared statements, input validation, and strong password policies.(159 characters)
