Mysql InnoDB bufferpool_MySQL-Mysql Tutorial-php.cn

Home

Database

Mysql Tutorial

Mysql InnoDB bufferpool_MySQL

WBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWBOYWB

Jun 01, 2016 pm 01:36 PM

insertupdateblogfriend

bitsCN.com

Mysql InnoDB bufferpool

今博客一位朋友找到问这个问题，上网找出以下的解释，希望能帮到他使用

问题：

发现在bufferpool用完后，insert完成后提交，select和update操作时数据如果不在bufferpool里，就需要从磁盘读，这时insert或者update操作会执行1s以上，导致那段时间的insert操作减少

innoDB在内存中维护一个缓存池用于缓存数据和索引。缓存池管理一个数据块列表，该列表又分为2个字列表，一个子列表存放new blocks，另一个子列表存放old blocks。old blocks默认占整个列表大小的3/8（可通过innodb_old_blocks_pct改变默认值，该值范围在5-95之间，这是一个百分比），其余大小为new blocks占用。

当有新数据添加到缓存池中时，如果缓存池的空间不足，则根据LRU算法清除数据。

-----重点解释

新插入缓存池的数据插入到存放old blocks的子列表的头部，如果数据被用户访问，则将这个数据移至new blocks的头部。如果设置了innodb_old_blocks_time大于0，比如innodb_old_blocks_time=1000，当新数据插入缓存池后过1s之后被访问，才会把数据移至new blocks的头部，在刚插入的一秒之内被访问改数据不会被移动，仍然在old blocks的头部。

------

www.bitsCN.com

当访问old blocks中的数据时，该数据会被移至new blocks的头部，但是当访问new blocks中的数据时，只有在该数据离new blocks的头部有一定距离时才移动。

为了更好的并发性能，通过指定innodb_buffer_pool_instances（该值取值范围为1-64）创建多个缓存池，每个缓存池的大小为

innodb_buffer_pool_size/innodb_buffer_pool_instances，通常需要保持当个缓存池的大小大于1GB。

bitsCN.com

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

What Are the Limitations of Using Views in MySQL?May 14, 2025 am 12:10 AM

MySQLviewshavelimitations:1)Theydon'tsupportallSQLoperations,restrictingdatamanipulationthroughviewswithjoinsorsubqueries.2)Theycanimpactperformance,especiallywithcomplexqueriesorlargedatasets.3)Viewsdon'tstoredata,potentiallyleadingtooutdatedinforma

Securing Your MySQL Database: Adding Users and Granting PrivilegesMay 14, 2025 am 12:09 AM

ProperusermanagementinMySQLiscrucialforenhancingsecurityandensuringefficientdatabaseoperation.1)UseCREATEUSERtoaddusers,specifyingconnectionsourcewith@'localhost'or@'%'.2)GrantspecificprivilegeswithGRANT,usingleastprivilegeprincipletominimizerisks.3)

What Factors Influence the Number of Triggers I Can Use in MySQL?May 14, 2025 am 12:08 AM

MySQLdoesn'timposeahardlimitontriggers,butpracticalfactorsdeterminetheireffectiveuse:1)Serverconfigurationimpactstriggermanagement;2)Complextriggersincreasesystemload;3)Largertablesslowtriggerperformance;4)Highconcurrencycancausetriggercontention;5)M

MySQL: Is it safe to store BLOB?May 14, 2025 am 12:07 AM

Yes,it'ssafetostoreBLOBdatainMySQL,butconsiderthesefactors:1)StorageSpace:BLOBscanconsumesignificantspace,potentiallyincreasingcostsandslowingperformance.2)Performance:LargerrowsizesduetoBLOBsmayslowdownqueries.3)BackupandRecovery:Theseprocessescanbe

MySQL: Adding a user through a PHP web interfaceMay 14, 2025 am 12:04 AM

Adding MySQL users through the PHP web interface can use MySQLi extensions. The steps are as follows: 1. Connect to the MySQL database and use the MySQLi extension. 2. Create a user, use the CREATEUSER statement, and use the PASSWORD() function to encrypt the password. 3. Prevent SQL injection and use the mysqli_real_escape_string() function to process user input. 4. Assign permissions to new users and use the GRANT statement.

MySQL: BLOB and other no-sql storage, what are the differences?May 13, 2025 am 12:14 AM

MySQL'sBLOBissuitableforstoringbinarydatawithinarelationaldatabase,whileNoSQLoptionslikeMongoDB,Redis,andCassandraofferflexible,scalablesolutionsforunstructureddata.BLOBissimplerbutcanslowdownperformancewithlargedata;NoSQLprovidesbetterscalabilityand

MySQL Add User: Syntax, Options, and Security Best PracticesMay 13, 2025 am 12:12 AM

ToaddauserinMySQL,use:CREATEUSER'username'@'host'IDENTIFIEDBY'password';Here'showtodoitsecurely:1)Choosethehostcarefullytocontrolaccess.2)SetresourcelimitswithoptionslikeMAX_QUERIES_PER_HOUR.3)Usestrong,uniquepasswords.4)EnforceSSL/TLSconnectionswith

MySQL: How to avoid String Data Types common mistakes?May 13, 2025 am 12:09 AM

ToavoidcommonmistakeswithstringdatatypesinMySQL,understandstringtypenuances,choosetherighttype,andmanageencodingandcollationsettingseffectively.1)UseCHARforfixed-lengthstrings,VARCHARforvariable-length,andTEXT/BLOBforlargerdata.2)Setcorrectcharacters

See all articles

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

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

How to fix KB5055612 fails to install in Windows 10?

4 weeks agoByDDD

Roblox: Grow A Garden - Complete Mutation Guide

3 weeks agoByDDD

Roblox: Bubble Gum Simulator Infinity - How To Get And Use Royal Keys

3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Nordhold: Fusion System, Explained

4 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Mandragora: Whispers Of The Witch Tree - How To Unlock The Grappling Hook

3 weeks agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

SublimeText3 Chinese version

Chinese version, very easy to use

DVWA

Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software