您好，mariadb 占用大量 CPU。设置在这里。服务器配备 CPU 6 核/12 线程 @ 3.4 GHz（4.8 GHz）
RAM 32GB DDR4 • ECC 服务器级
磁盘驱动器 2 x 480GB SSD SATA 软件 RAID
[client-server]
#
# include *.cnf from the config directory
#
!includedir /etc/my.cnf.d
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
key_buffer_size = 32M # from 23G whoa, likely an accident. only used by ISAM
back_log = 5
max_connections = 300
wait_timeout = 64
max_connect_errors = 10
table_open_cache = 2048
max_allowed_packet = 2M
binlog_cache_size = 512M
max_heap_table_size = 512M
thread_cache_size = 0
thread_concurrency = 8
thread_stack = 240K
query_cache_size = 64M
query_cache_limit = 2M
ft_min_word_len = 4
default-storage-engine = InnoDB
transaction_isolation = REPEATABLE-READ
tmp_table_size = 256M
log-bin=mysql-bin
binlog_format=mixed
slow_query_log
long_query_time = 2
server-id = 1
# INNODB options
innodb_buffer_pool_size = 64G
innodb_buffer_pool_instances = 8
innodb_data_file_path = ibdata1:10M:autoextend
innodb_write_io_threads = 8
innodb_read_io_threads = 8
innodb_thread_concurrency = 16
innodb_flush_log_at_trx_commit = 1
innodb_log_buffer_size = 1GB
innodb_change_buffering = all
innodb_change_buffer_max_size = 25
innodb_log_file_size = 512M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_lock_wait_timeout = 256
unix_socket=OFF
[mysqldump]
quick
max_allowed_packet = 50M
[mysql]
no-auto-rehash
[mysqlhotcopy]
interactive-timeout
[mysqld_safe]
open-files-limit = 8192
thread_handling=pool-of-threads # from one-thread-per-connection for scalability
max_heap_table_size=512M # from 16M to increase RAM capacity
tmp_table_size=512M # from 256K 2 be = max_heap_table_size and reduce created_tmp_disk_tables
innodb_io_capacity=5000 # from 200 limit for SSD possible RPS
read_buffer_size=256K # from 128K to reduce handler_read_next RPS
read_rnd_buffer_size=256K # from 256K to reduce handler_read_rnd_nxt RPS
aria_pagecache_division_limit=50 # from 100 for WARM cache
key_cache_division_limit=50 # from 100 for WARM cache
innodb_buffer_pool_instances=8 # from 12 for your current data volume
innodb_buffer_pool_size=24G # from 64G to support 11G of data with room to grow
innodb_lru_scan_depth=200 # from 1024 to reduce CPU every SECOND see refman
innodb_thread_concurrency=0 # from 8 see dba.stackexchange Question 5666
[client-server]
答案1
MySQL 的 CPU 使用率达到 300% 可能是正常的。
真正的问题是什么？如果您尝试解决慢速查询问题，则应记录它们，然后进行分析。激活slow_query_log、运行SHOW FULL PROCESSLIST和SHOW ENGINE INNODB STATUS\G以概览 MySQL，使用mysqldumpslow和分析慢速日志pt-query-digest，使用EXPLAIN FORMAT=TREE和EXPLAIN ANALYZE分析查询。
正如 @AlexD 提到的，innodb_buffer_pool_size当 MySQL 停止时，应该低于可用内存。例如，如果您停止 MySQL 并且有 28GB 可用，则可以设置innodb_buffer_pool_size为大约 25GB。不要从互联网上复制粘贴 MySQL 配置，而要理解它们，并且要验证它们是否与您的用例（OLAP 与 OLTP、更多写入或更多读取...）、使用的 DB 存储引擎（InnoDB、MyISAM...）以及您的 MySQL 版本相关。