今天我遇到一个问题,MySQL企业版备份引起I/O子系统负载过大,应用响应缓慢,导致系统不可用。所以我想限制mysqlbackup的进程,使
今天我遇到一个问题,MySQL企业版备份引起I/O子系统负载过大,应用响应缓慢,导致系统不可用。所以我想限制mysqlbackup的进程,使它不会引起更多的问题。
mysqlbackup命令里面有读,,写和进程数的设置。默认是1个读,1个写和5个线程。因为我用的是默认设置,所以还是没有必要去调整了。
使用ionice工具没法工作,因为它需要CFG I/O调度器。
我在这篇文章里找到一个方法。 它使用的是linux的cgroups。之前,在三台中有一台服务器使用的是非常慢的CPU的情况下,我使用过cgroups来测试一个galera的安装工作。
# mkdir /cgroup/blkio
# mount -t cgroup -o blkio non /cgroup/blkio
# cgcreate -g blkio:/mysqlbackup
# ls -lh /dev/mapper/vgdb01-lvdb01
lrwxrwxrwx 1 root root 7 Sep 26 14:22 /dev/mapper/vgdb01-lvdb01 -> ../dm-2
# ls -lh /dev/dm-2
brw-rw---- 1 root disk 253, 2 Sep 26 14:22 /dev/dm-2
# cgset -r blkio.throttle.read_iops_device="253:2 20" mysqlbackup
# cgset -r blkio.throttle.write_iops_device="253:2 20" mysqlbackup
# echo $$ > /cgroup/blkio/mysqlbackup/tasks
# cat /proc/$$/cgroup
1:blkio:/mysqlbackup
# mysqlbackup --user=root --password=xxxxxx --with-timestamp --backup-dir=/data/backup backup
和我期待的完全一样,这种方式工作的很好。读和写操作都被限制在 20 iops.
后来发现是存储系统的问题,所以我没有在生产环境使用这种方法,但是我希望这会帮上其他人忙。或许在其他问题下也是有用的。
本文永久更新链接地址:

Stored procedures are precompiled SQL statements in MySQL for improving performance and simplifying complex operations. 1. Improve performance: After the first compilation, subsequent calls do not need to be recompiled. 2. Improve security: Restrict data table access through permission control. 3. Simplify complex operations: combine multiple SQL statements to simplify application layer logic.

The working principle of MySQL query cache is to store the results of SELECT query, and when the same query is executed again, the cached results are directly returned. 1) Query cache improves database reading performance and finds cached results through hash values. 2) Simple configuration, set query_cache_type and query_cache_size in MySQL configuration file. 3) Use the SQL_NO_CACHE keyword to disable the cache of specific queries. 4) In high-frequency update environments, query cache may cause performance bottlenecks and needs to be optimized for use through monitoring and adjustment of parameters.

The reasons why MySQL is widely used in various projects include: 1. High performance and scalability, supporting multiple storage engines; 2. Easy to use and maintain, simple configuration and rich tools; 3. Rich ecosystem, attracting a large number of community and third-party tool support; 4. Cross-platform support, suitable for multiple operating systems.

The steps for upgrading MySQL database include: 1. Backup the database, 2. Stop the current MySQL service, 3. Install the new version of MySQL, 4. Start the new version of MySQL service, 5. Recover the database. Compatibility issues are required during the upgrade process, and advanced tools such as PerconaToolkit can be used for testing and optimization.

MySQL backup policies include logical backup, physical backup, incremental backup, replication-based backup, and cloud backup. 1. Logical backup uses mysqldump to export database structure and data, which is suitable for small databases and version migrations. 2. Physical backups are fast and comprehensive by copying data files, but require database consistency. 3. Incremental backup uses binary logging to record changes, which is suitable for large databases. 4. Replication-based backup reduces the impact on the production system by backing up from the server. 5. Cloud backups such as AmazonRDS provide automation solutions, but costs and control need to be considered. When selecting a policy, database size, downtime tolerance, recovery time, and recovery point goals should be considered.

MySQLclusteringenhancesdatabaserobustnessandscalabilitybydistributingdataacrossmultiplenodes.ItusestheNDBenginefordatareplicationandfaulttolerance,ensuringhighavailability.Setupinvolvesconfiguringmanagement,data,andSQLnodes,withcarefulmonitoringandpe

Optimizing database schema design in MySQL can improve performance through the following steps: 1. Index optimization: Create indexes on common query columns, balancing the overhead of query and inserting updates. 2. Table structure optimization: Reduce data redundancy through normalization or anti-normalization and improve access efficiency. 3. Data type selection: Use appropriate data types, such as INT instead of VARCHAR, to reduce storage space. 4. Partitioning and sub-table: For large data volumes, use partitioning and sub-table to disperse data to improve query and maintenance efficiency.

TooptimizeMySQLperformance,followthesesteps:1)Implementproperindexingtospeedupqueries,2)UseEXPLAINtoanalyzeandoptimizequeryperformance,3)Adjustserverconfigurationsettingslikeinnodb_buffer_pool_sizeandmax_connections,4)Usepartitioningforlargetablestoi


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

Hot Tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

Zend Studio 13.0.1
Powerful PHP integrated development environment

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

SublimeText3 Linux new version
SublimeText3 Linux latest version

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
