Ubuntu WebServer Disk Space augmente soudainement

Nous avons un service Cloud iWstack, avec un espace principal de 100 Go et 20 Go de Side Storge.

NewRelic me dit toujours que l’espace principal est plein.

Je vérifie ce qui utilise cet espace avec:

sudo du -a /var/www | sort -n

mais tout semble sain.

puis je commence à vider le cache tout autour.

et remarquez que quand je le fais:

RESET QUERY CACHE; RESET MASTER;

et redémarrer NGINX et PHP5 permettra de libérer de l’espace.

Y at-il une configuration sur my.cnf qui me manque ???

METTRE À JOUR

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 ensortinges 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 = /media/db/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 = 100 connect_timeout = 5 wait_timeout = 600 max_allowed_packet = 16M thread_cache_size = 128 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 = BACKUP key_buffer_size = 128M #open-files-limit = 2000 table_open_cache = 400 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 = 128K query_cache_size = 64M # for more write intensive setups, set to DEMAND or OFF #query_cache_type = DEMAND # # * 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 ssortingcter 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 = 256M innodb_log_buffer_size = 8M innodb_file_per_table = 1 innodb_open_files = 400 innodb_io_capacity = 400 innodb_flush_method = O_DIRECT # # * Security Features # # Read the manual, too, if you want chroot! # chroot = /var/lib/mysql/ # # For generating SSL certificatees 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 [mysqldump] quick quote-names max_allowed_packet = 16M [mysql] #no-auto-rehash # faster start of mysql but no tab completition [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/ 

Le cache de requêtes MySQL a été conçu à l’origine il y a 13 ans. Depuis, il n’a pas été adapté aux nouveaux logiciels et matériels. En raison de la recommandation des experts de Percona, désactivez-la tout le temps:

query_cache_size: le cache de requêtes est un goulot d’étranglement bien connu, même lorsque la concurrence est modérée. La meilleure option est de le désactiver à partir du jour 1 en définissant query_cache_size = 0 (désormais la valeur par défaut sur MySQL 5.6) et d’utiliser d’autres moyens pour accélérer les requêtes de lecture: indexation correcte, ajout de répliques pour répartir la charge ou utiliser un cache externe.

Mais il s’agit d’une recommandation de performances pure, le cache de requêtes ne consum pas d’espace disque jusqu’à ce qu’il soit réellement échangé.

Qu’est-ce que la réinitialisation du maître fait pour vous, MySQL docs dit :

RESET MASTER supprime tous les fichiers journaux binarys répertoriés dans le fichier d’index, ne laissant qu’un seul fichier journal binary vide avec un suffixe numérique de .000001, alors que la numérotation n’est pas réinitialisée par PURGE BINARY LOGS.

Partagez votre configuration my.cnf pour obtenir des instructions plus détaillées, mais si vous dites Reset Master, les journaux binarys ne sont pas configurés correctement.