높은 CPU 소비량 MySQL

높은 CPU 소비량 MySQL

easyengine + wp + redis를 갖춘 워드프레스 뉴스 포털을 가지고 있는데, 퍼포먼스 문제가 있는 날이 며칠이 되면 mysql이 CPU 사용량을 많이 소비합니다.이 문제를 해결하기 위해 50만 명 이상의 게시물을 올립니다.

print cpu https://prnt.sc/jgkpwy

서버 상세 Ubuntu 16.04 - 최소 - RAID 1 하드디스크 256 GB SSD 2.5 인치 하드디스크 256 GB SSD 2.5 인치 RAM 32 GB CPU Intel Xeon E3-1225v3

mysql 설정 my.cnf

# MariaDB database server configuration file.
#
# You can copy this file to one of:
# - "/etc/mysql/my.cnf" to set global options,
# - "~/.my.cnf" to set user-specific options.
# 
# One can use all long options that the program supports.
# Run program with --help to get a list of available options and with
# --print-defaults to see which it would actually understand and use.
#
# For explanations see
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port		= 3306
socket		= /var/run/mysqld/mysqld.sock

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket		= /var/run/mysqld/mysqld.sock
nice		= 0

[mysqld]
#
# * Basic Settings
#
user		= mysql
pid-file	= /var/run/mysqld/mysqld.pid
socket		= /var/run/mysqld/mysqld.sock
port		= 3306
basedir		= /usr
datadir		= /var/lib/mysql
tmpdir		= /tmp
lc_messages_dir	= /usr/share/mysql
lc_messages	= en_US
skip-external-locking
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
#bind-address		= 127.0.0.1
#
# * Fine Tuning
#
max_connections		= 300
connect_timeout		= 5
wait_timeout		= 600
max_allowed_packet	= 16M
thread_cache_size       = 500
sort_buffer_size	= 4M
bulk_insert_buffer_size	= 16M
tmp_table_size		= 32M
max_heap_table_size	= 32M
#
# * MyISAM
#
# This replaces the startup script and checks MyISAM tables if needed
# the first time they are touched. On error, make copy and try a repair.
myisam_recover_options = BACKUP
key_buffer_size		= 128M
#open-files-limit	= 2000
table_open_cache	= 600
myisam_sort_buffer_size	= 512M
concurrent_insert	= 2
read_buffer_size	= 2M
read_rnd_buffer_size	= 1M
#
# * Query Cache Configuration
#
# Cache only tiny result sets, so we can fit more in the query cache.
query_cache_limit		= 2M
query_cache_size		= 256M
query_cache_strip_comments =1
# for more write intensive setups, set to DEMAND or OFF
query_cache_type		= 1
#
# * Logging and Replication
#
# Both location gets rotated by the cronjob.
# Be aware that this log type is a performance killer.
# As of 5.1 you can enable the log at runtime!
#general_log_file        = /var/log/mysql/mysql.log
#general_log             = 1
#
# Error logging goes to syslog due to /etc/mysql/conf.d/mysqld_safe_syslog.cnf.
#
# we do want to know about network errors and such
log_warnings		= 2
#
# Enable the slow query log to see queries with especially long duration
#slow_query_log[={0|1}]
slow_query_log_file	= /var/log/mysql/mariadb-slow.log
long_query_time = 10
#log_slow_rate_limit	= 1000
log_slow_verbosity	= query_plan

#log-queries-not-using-indexes
#log_slow_admin_statements
#
# The following can be used as easy to replay backup logs or for replication.
# note: if you are setting up a replication slave, see README.Debian about
#       other settings you may need to change.
#server-id		= 1
#report_host		= master1
#auto_increment_increment = 2
#auto_increment_offset	= 1
#log_bin			= /var/log/mysql/mariadb-bin
#log_bin_index		= /var/log/mysql/mariadb-bin.index
# not fab for performance, but safer
#sync_binlog		= 1
#expire_logs_days	= 10
#max_binlog_size         = 100M
# slaves
#relay_log		= /var/log/mysql/relay-bin
#relay_log_index	= /var/log/mysql/relay-bin.index
#relay_log_info_file	= /var/log/mysql/relay-bin.info
#log_slave_updates
#read_only
#
# If applications support it, this stricter sql_mode prevents some
# mistakes like inserting invalid dates etc.
#sql_mode		= NO_ENGINE_SUBSTITUTION,TRADITIONAL
#
# * InnoDB
#
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/.
# Read the manual for more InnoDB related options. There are many!
default_storage_engine	= InnoDB
# you can't just change log file size, requires special procedure
#innodb_log_file_size	= 50M
innodb_buffer_pool_size	= 15G
innodb_log_buffer_size	= 16M
innodb_file_per_table	= 1
innodb_open_files	= 400
innodb_io_capacity	= 400
innodb_flush_method	= O_DIRECT
innodb_buffer_pool_instances	= 15
#
# * Security Features
#
# Read the manual, too, if you want chroot!
# chroot = /var/lib/mysql/
#
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca".
#
# ssl-ca=/etc/mysql/cacert.pem
# ssl-cert=/etc/mysql/server-cert.pem
# ssl-key=/etc/mysql/server-key.pem

#
# * Galera-related settings
#
[galera]
# Mandatory settings
#wsrep_on=ON
#wsrep_provider=
#wsrep_cluster_address=
#binlog_format=row
#default_storage_engine=InnoDB
#innodb_autoinc_lock_mode=2
#
# Allow server to accept connections on all interfaces.
#
#bind-address=0.0.0.0
#
# Optional setting
#wsrep_slave_threads=1
#innodb_flush_log_at_trx_commit=0

[mysqldump]
quick
quote-names
max_allowed_packet	= 16M

[mysql]
#no-auto-rehash	# faster start of mysql but no tab completion

[isamchk]
key_buffer		= 16M

#
# * IMPORTANT: Additional settings that can override those from this file!
#   The files must end with '.cnf', otherwise they'll be ignored.
#
!includedir /etc/mysql/conf.d/

my.cnf-ini [mysqld]섹션에서 고려해야 할 권장 사항

sort_buffer_size=4M  # REMOVE or LEAD with # for default
read_buffer_size=2M  # REMOVE or LEAD with # for default
read_rnd_buffer_size=1M  # REMOVE or LEAD with # for default
innodb_buffer_pool_instances=8  # from 15 will be adequate
thread_cache_size=100  # from 500 see V8 refman CAP at 100 to avoid OOM
innodb_lru_search_depth=128  # from 1024 to be = innodb_buffer_pool_instances
innodb_purge_threads=4  # from likely 1 to support DELETE cleanup
max_write_lock_count=16  # from HUGE # to conserve CPU cycles
query_cache_min_res_unit=512  # from 4096 to support more QC results

진행상황에 대해 계속 알려주세요.

ulimit -a 및 SHOW GLOBAL STATUS의 텍스트 결과를 게시하고 SHOW GLOBAL VARIAS를 게시하면 도움이 되는 추가 제안을 제공할 수 있습니다.

my.cnf-ini [mysqld]섹션 제안
SET GLOBAL variable_name= value를 사용한 후 다음 변수로 이동하기 전에 1분간 정확하고 허용 가능한 제한을 실행하려면 다음 SET GLOBAL 전에 항상 오류 로그를 확인하여 피해가 없는지 확인한 다음 목록의 끝에 있는 성공적인 변수 값으로 my.cnf-ini를 편집하십시오.

innodb_buffer_pool_size=18*1024*1024*1024  # from 15G for growth
innodb_io_capacity=1000  # from 400 for additional IOPS capacity
read_rnd_buffer_size=128*1024  # from 256K to reduce handler_read_rnd_next
read_buffer_size=256*1024  # from 128K to reduce handler_read_rnd
tmp_table_size=128*1024*1024  # from 32M to expand tmp RAM tbls
max_heap_table_size=128*1024*1024  # from 32M to reduce created_tmp_disk_tables
innodb_lru_scan_depth=128  # from 1024 to reduce CPU use
query_cache_size=50*1024*1024  # from 256M to reduce QC overhead on CPU
query_cache_limit=512*1024  # from 2M for max query result to be stored
updatable_views_with_limit=0  # from YES to reduce handler_external_lock

UVWL은 YES를 유지해야 할 수 있습니다. 참조.

Skype 및 teamviewer를 통해 귀사의 테스트 및 구현 상황을 관찰하고 싶습니다.가능하다면 오늘(조기)입니다.

my.cnf-ini [mysqld]의 기타 변경사항은 다음과 같습니다.

thread_concurrency=30  # from 10 to allow more concurrency
expire_logs_days=5  # from 0 for limited historical logs
key_cache_age_threshold=64800  # from 300 seconds discard to RD again
key_cache_division_limit=50  # for HOT and WARM usage boundary
key_cache_block_size=16384  # from 1024 to age out larger size  

추가 분석을 통해 더 많은 기회를 찾을 수 있습니다.

말씀하신 모든 느린 쿼리는wp_postmetaWP는 그 테이블에 대해 매우 비효율적인 스키마를 가지고 있다.여기에 몇 가지 수정 사항을 개략적으로 설명하겠습니다.그 스키마를 개선한 후에도 문제가 있는 경우는, 향후의 순서에 대해 논의해 주세요.

CPU의 고부하 문제는 튜닝할 수 없습니다.다만, 너무 높은 설정이 1개 있습니다.

query_cache_size = 256M -- Change to 50M

읽기 쉽도록 하기 위해 느린 쿼리 중 하나를 다음에 나타냅니다.

SELECT  wp_posts.ID
    FROM  wp_posts
    LEFT JOIN  wp_term_relationships
          ON ( wp_posts.ID = wp_term_relationships.object_id)
    INNER JOIN  wp_postmeta  ON ( wp_posts.ID = wp_postmeta.post_id )
    INNER JOIN  wp_postmeta AS mt1  ON ( om16_posts.ID = mt1.post_id )
    WHERE  1=1
      AND  ( wp_term_relationships.term_taxonomy_id IN (19,37, 38,72) )
      AND  ( wp_postmeta.meta_key = '_thumbnail_id'
              AND  ( mt1.meta_key = 'exibir_menu'
                      AND  mt1.meta_value = '1' ) 
           )
      AND  wp_posts.post_type = 'post'
      AND  ((wp_posts.post_status = 'publish'))
    GROUP BY  wp_posts.ID
    ORDER BY  wp_posts.post_date DESC
    LIMIT  0, 7 

사용하세요-s t사용할 때mysqldump.

부칙

이 경우:

CREATE TABLE `om16_postmeta` (
  `meta_id` bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  `post_id` bigint(20) unsigned NOT NULL DEFAULT '0',
  `meta_key` varchar(255) COLLATE utf8_unicode_ci DEFAULT NULL,
  `meta_value` longtext COLLATE utf8_unicode_ci,
  PRIMARY KEY (`meta_id`),
  KEY `post_id` (`post_id`),
  KEY `idx_meta_key` (`meta_key`(50)),
  KEY `meta_key` (`meta_key`(191))

이를 통해 최소한의 노력으로 최대의 이점을 얻을 수 있습니다.

ALTER TABLE om16_postmeta
    DROP PRIMARY KEY,
    DROP INDEX post_id,
    ADD PRIMARY KEY(post_id, meta_key),  -- much better for queries
    ADD INDEX(meta_id),         -- sufficient for AUTO_INCREMENT
    DROP INDEX idx_meta_key,    -- prefix indexing unnecessary an inefficient
    DROP INDEX meta_key,
    ADD INDEX(meta_key);

주의:이 작업을 수행하려면 시간이 좀 걸릴 것 같습니다.ALTER; 테이블이 차단됩니다.

만약 그렇다면ALTER「복제 키」로 이어집니다만, 특정의 「투고」에 대해서, 같은 「키」를 몇번이나 가지고 있는 것을 알 수 있습니다.어느 하나

• 데이터 입력에 오류가 있습니다.이 경우 데이터를 정리해야 합니다.아니면...
• 메타키을 PK로 합니다.ADD PRIMARY KEY(post_id, meta_key, meta_id),.

언급URL : https://stackoverflow.com/questions/50294741/high-cpu-consumption-mysql