Not the answer you need?
Register and ask your own question!

Mysql high cpu usage (over 600%)

antoniodilorenzoantoniodilorenzo EntrantLegacy User Role Beginner
Here is my mysql configuration file:
# # The MySQL database server configuration file. # # You can copy this 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. # Here is entries for some specific programs # The following values assume you have at least 32M ram [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 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 # innodb_buffer_pool_size = 12G key_buffer_size = 1G max_allowed_packet = 256M thread_stack = 192K thread_cache_size = 8 # This replaces the startup script and checks MyISAM tables if needed # the first time they are touched myisam-recover-options = BACKUP max_connections = 300 #innodb_buffer_pool_instances=8 #innodb_read_io_threads=8 #innodb_write_io_threads=8 #open_files_limit = 1024 #table_open_cache = 400 server_id = 2 bind-address = 0.0.0.0 log_bin = /var/log/mysql/mysql-bin.log log_bin_index = /var/log/mysql/mysql-bin.log.index relay_log = /var/log/mysql/mysql-relay-bin relay_log_index = /var/log/mysql/mysql-relay-bin.index expire_logs_days = 10 max_binlog_size = 100M log_slave_updates = 1 auto-increment-increment = 2 auto-increment-offset = 2 replicate-ignore-db=phpmyadmin replicate-ignore-db=mysql skip-name-resolve #table_cache = 64 #thread_concurrency = 10 # # * Query Cache Configuration # query_cache_limit = 0 query_cache_size = 0 sort_buffer_size = 1M join_buffer_size = 1M read_buffer_size = 1M # # * 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 log - should be very few entries. # log_error = /var/log/mysql/error.log # # Here you can see queries with especially long duration #log_slow_queries = /var/log/mysql/mysql-slow.log #long_query_time = 2 #log-queries-not-using-indexes # # 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 #log_bin = /var/log/mysql/mysql-bin.log expire_logs_days = 10 max_binlog_size = 100M #binlog_do_db = include_database_name #binlog_ignore_db = include_database_name # # * 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! # # * 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
The server has 8core CPU and 22 GB of ram. Every day receives many requests from users, and recently a replication mechanism has been activated, with an implementation of a db master and a slave. Now the server is really slow (on ssh top, mysqld reaches 600% and more of CPU Usage) and sometimes it go down of service. Please can you help me to fix this issue?

Comments

  • przemekprzemek Percona Support Engineer Percona Staff Role
    The config file alone is not enough to tell anything what sort of problems you have. High CPU usage may be due to heavy queries taking long time, but also there may be high IO wait or just too high concurrency.
    Ideally, you should collect more details running pt-stalk tool during the peak time, or configure PMM monitoring, which will provide great level of details with history graphs. Both tools are free.
Sign In or Register to comment.

MySQL, InnoDB, MariaDB and MongoDB are trademarks of their respective owners.
Copyright ©2005 - 2020 Percona LLC. All rights reserved.