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Je passe une application (hotline pour nos clients) qui fonctionne sur Java avec un DB2 BDD (sur une bête de course AS400) vers un BDD MariaDB fonctionnant sur un serveur Unix. J'ai un problème de performances. Le nouveau serveur Unix dispose de deux processeurs * 1 core et 5Go de RAM. Je pourrais négocier 2 coeurs plus mais guère plus loin. L'application peut être sollicitée par 100 utilisateurs/jour, et 10-15 utilisateurs actifs en même temps. Ma table principale a 20000 enregistrements (nombre de tickets hotline) mais les tables dépendantes peuvent atteindre environ 150 000 enregistrements. J'utilise le moteur InnoDB, car je suis obligé de garder les contraintes des clés étrangères. J'ai créé les index les plus logiques. Chaque table a une moyenne de 50 champs. (Decimal et varchar 10 ou 20) Le problème est que j'ai des requêtes avec 5 vues qui utilisent 4 tables chacune (voir les autres vues), ce qui est très gourmand avec plusieurs dizaines de milliers d'enregistrements par table. Je peux difficilement modifier ces requêtes à moins que je réécris complètement l'application. (Je vous rappelle que c'est juste un changement de BDD). Quelqu'un peut-il me dire si le réglage my.cnf est OK ou non. Je suis à la recherche d'infos sur le web mais je ne suis pas un expert.Base de données de paramètres MariaDB 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
lower_case_table_names = 1
character-set-server=utf8
collation-server=utf8_general_ci
#
# Instead of skip-networking the default is now to listen only on
# localhost which is more compatible and is not less secure.
bind-address = 10.10.64.51
#
# * Fine Tuning
#
max_connections = 100
connect_timeout = 5
wait_timeout = 600
max_allowed_packet = 16M
thread_cache_size = 128
#sort_buffer_size = 4M
sort_buffer_size = 8M
bulk_insert_buffer_size = 16M
#tmp_table_size = 32M
#max_heap_table_size = 32M
#tmp_table_size = 256M
tmp_table_size = 512M
#max_heap_table_size = 256M
max_heap_table_size = 512M
#
# * 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 = 400
table_open_cache = 600
myisam_sort_buffer_size = 512M
concurrent_insert = 2
read_buffer_size = 2M
#read_rnd_buffer_size = 1M
read_rnd_buffer_size = 2M
#
# * Query Cache Configuration
#
# Cache only tiny result sets, so we can fit more in the query cache.
#query_cache_limit = 128K
query_cache_limit = 512K
#query_cache_size = 256M
query_cache_size = 512M
#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 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 = 256M
#innodb_buffer_pool_size = 512M
innodb_buffer_pool_size = 1G
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 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/
Meilleures salutations
Avez-vous exécuté vous-même des tests utilisant différents paramètres? –
Vos utilisateurs souffrent-ils de problèmes de performances? Savez-vous que MariaDB ne gère pas les "vues matérialisées" * out-of-the-box? Savez-vous que MariaDB ne peut pas utiliser plus d'un index par table dans une requête, et bénéficie donc souvent d'indices de couverture composés bien choisis? Votre meilleur pari pour l'optimisation peut être d'étudier le * journal de requête lent *, d'identifier les requêtes les plus lentes et de les optimiser en ajoutant des index appropriés. –
C'est vraiment cool qu'un port de DB2/AS400 vers MariaDB fonctionne! –