统计Oracle读块的IO能力-Mysql Tutorial-php.cn

Home

Database

Mysql Tutorial

统计Oracle读块的IO能力

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 07, 2016 pm 05:14 PM

忽然想到了测试数据库的真实IO能力,虽然硬件工程师有套方法测试IOPS ,虽然ORACLE也推出了ORAXXX的测试小工具. 实际应用环境中因

忽然想到了测试数据库的真实IO能力,虽然硬件工程师有套方法测试IOPS ,虽然Oracle也推出了ORAXXX的测试小工具. 实际应用环境中因为表空间,表的设置,块的大小等因素影响到IOPS. 比如想一个全表扫描,需要多久才能出来呢? 分别在工作负责空闲情况下,高的情况下,并行的情况下.

做公司的研发数据库上做了相应的实验,就在空闲情况下得到的时间不太有效.

比如一个表有1万个块,每个块8K 得到公司的IO能力每秒285M; 36480块. 总觉得 ALTER SYSTEM FLUSH BUFFER_CACHE 和 SHARED_POOL 清空内存总是无效样.

在家里做相应的实验启动了作用.

用一个384个块的表 SELET COUNT(*) FROM T_TEST

FLUSH BUFFER_CACHE 和 SHARED_POOL 波动范围 0.329 ,0.297 0.266 秒

flush shared_pool; --0.187
flush buffer_cache; --0.172 0.156 秒

那么IO能力是: 384/0.172*8/1024=17.44M

使用并行提示 /*+parallel(t,4)*/ /*+parallel(t,3)*/ /*+parallel(t,2)*/

分别得到时间: 0.64 0.375 0.296 看来单CPU的并行能力很耗时间的.

内存读是多少了. 只要重复执行下就便晓得了而得到时间是 0.031和0.015

内存IO: 96.77M和200M

linux

，

Statement

The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

How do you alter a table in MySQL using the ALTER TABLE statement?Mar 19, 2025 pm 03:51 PM

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

How do I configure SSL/TLS encryption for MySQL connections?Mar 18, 2025 pm 12:01 PM

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]

How do you handle large datasets in MySQL?Mar 21, 2025 pm 12:15 PM

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

What are some popular MySQL GUI tools (e.g., MySQL Workbench, phpMyAdmin)?Mar 21, 2025 pm 06:28 PM

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

How do you drop a table in MySQL using the DROP TABLE statement?Mar 19, 2025 pm 03:52 PM

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.

How do you create indexes on JSON columns?Mar 21, 2025 pm 12:13 PM

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.

How do you represent relationships using foreign keys?Mar 19, 2025 pm 03:48 PM

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

How do I secure MySQL against common vulnerabilities (SQL injection, brute-force attacks)?Mar 18, 2025 pm 12:00 PM

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

See all articles