Ich habe einen Webserver unter RHEL, auf dem Apache und MySQL laufen. Es hat eine Quad Core 3.2Ghz Xeon CPU und 8 GB RAM. Die meiste Zeit haben wir überhaupt keine Probleme.Wie kann ich mysqld mehr als 24,9% meiner CPU verwenden?
Unsere Webanwendung ist sehr datenbankintensiv. Wenn unsere Verwendung ziemlich schwer wird, wird MySQL 24,9% der CPU verwenden. Die meiste Zeit liegt es unter 5%. Ich habe spekuliert, dass es nur einen Kern der CPU verwendet und es diesen Kern heraushängt, aber TOP zeigt mir in der CPU-Spalte, dass mysqld die Kerne ändert, selbst wenn die Nutzung bei 24,9% bleibt. Wenn es das tut, wird MySQL schmerzhaft langsam, da es Anfragen in die Warteschlange stellt. Gibt es eine magische Konfiguration, die mysql anweist, mehr CPU zu verwenden, wenn es nötig ist? Außerdem wäre jeder andere Hinweis zu meiner Konfiguration hilfreich.
Wir führen zwei Anwendungen auf diesem Server aus. Einer, der Innodb ausführt, aber nicht viel benutzt wird (er wurde durch die andere App ersetzt), und einer, der MyIsam ausführt und viel benutzt wird. Alles in allem ist unser gesamtes mysql-Datenverzeichnis etwas wie 13Gigs, wenn das überhaupt zählt.
Hier ist meine config:
[[email protected] root]# cat /etc/my.cnf [mysqld] server-id = 71 log-bin = /var/log/mysql/mysql-bin.log binlog-do-db = oldapplication binlog-do-db = newapplication binlog-do-db = support thread_cache_size = 30 key_buffer_size = 256M table_cache = 256 sort_buffer_size = 4M read_buffer_size = 1M skip-name-resolve innodb_data_home_dir = /usr/local/mysql/data/ innodb_data_file_path = InnoDB:100M:autoextend set-variable = innodb_buffer_pool_size=70M set-variable = innodb_additional_mem_pool_size=10M set-variable = max_connections=500 innodb_log_group_home_dir = /usr/local/mysql/data innodb_log_arch_dir = /usr/local/mysql/data set-variable = innodb_log_file_size=20M set-variable = innodb_log_buffer_size=8M innodb_flush_log_at_trx_commit = 1 log-queries-not-using-indexes log-error = /var/log/mysql/mysql-error.log
Alle hier helfen?
mysql> show variables; +---------------------------------+-----------------------------------------------------------------------------+ | Variable_name | Value | +---------------------------------+-----------------------------------------------------------------------------+ | auto_increment_increment | 1 | | auto_increment_offset | 1 | | automatic_sp_privileges | ON | | back_log | 50 | | basedir | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/ | | binlog_cache_size | 32768 | | bulk_insert_buffer_size | 8388608 | | character_set_client | latin1 | | character_set_connection | latin1 | | character_set_database | latin1 | | character_set_results | latin1 | | character_set_server | latin1 | | character_set_system | utf8 | | character_sets_dir | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/share/mysql/charsets/ | | collation_connection | latin1_swedish_ci | | collation_database | latin1_swedish_ci | | collation_server | latin1_swedish_ci | | completion_type | 0 | | concurrent_insert | 1 | | connect_timeout | 5 | | datadir | /usr/local/mysql/data/ | | date_format | %Y-%m-%d | | datetime_format | %Y-%m-%d %H:%i:%s | | default_week_format | 0 | | delay_key_write | ON | | delayed_insert_limit | 100 | | delayed_insert_timeout | 300 | | delayed_queue_size | 1000 | | div_precision_increment | 4 | | engine_condition_pushdown | OFF | | expire_logs_days | 0 | | flush | OFF | | flush_time | 0 | | | ft_max_word_len | 84 | | ft_min_word_len | 4 | | ft_query_expansion_limit | 20 | | ft_stopword_file | (built-in) | | group_concat_max_len | 1024 | | have_archive | YES | | have_bdb | NO | | have_blackhole_engine | NO | | have_compress | YES | | have_crypt | YES | | have_csv | NO | | have_example_engine | NO | | have_federated_engine | NO | | have_geometry | YES | | have_innodb | YES | | have_isam | NO | | have_ndbcluster | NO | | have_openssl | NO | | have_query_cache | YES | | have_raid | NO | | have_rtree_keys | YES | | have_symlink | YES | | init_connect | | | init_file | | | init_slave | | | innodb_additional_mem_pool_size | 10485760 | | innodb_autoextend_increment | 8 | | innodb_buffer_pool_awe_mem_mb | 0 | | innodb_buffer_pool_size | 73400320 | | innodb_checksums | ON | | innodb_commit_concurrency | 0 | | innodb_concurrency_tickets | 500 | | innodb_data_file_path | InnoDB:100M:autoextend | | innodb_data_home_dir | /usr/local/mysql/data/ | | innodb_doublewrite | ON | | innodb_fast_shutdown | 1 | | innodb_file_io_threads | 4 | | innodb_file_per_table | OFF | | innodb_flush_log_at_trx_commit | 1 | | innodb_flush_method | | | innodb_force_recovery | 0 | | innodb_lock_wait_timeout | 50 | | innodb_locks_unsafe_for_binlog | OFF | | innodb_log_arch_dir | /usr/local/mysql/data | | innodb_log_archive | OFF | | innodb_log_buffer_size | 8388608 | | innodb_log_file_size | 20971520 | | innodb_log_files_in_group | 2 | | innodb_log_group_home_dir | /usr/local/mysql/data | | innodb_max_dirty_pages_pct | 90 | | innodb_max_purge_lag | 0 | | innodb_mirrored_log_groups | 1 | | innodb_open_files | 300 | | innodb_support_xa | ON | | innodb_sync_spin_loops | 20 | | innodb_table_locks | ON | | innodb_thread_concurrency | 20 | | innodb_thread_sleep_delay | 10000 | | interactive_timeout | 28800 | | join_buffer_size | 131072 | | key_buffer_size | 268435456 | | key_cache_age_threshold | 300 | | key_cache_block_size | 1024 | | key_cache_division_limit | 100 | | language | /usr/local/mysql-standard-5.0.18-linux-x86_64-glibc23/share/mysql/english/ | | large_files_support | ON | | large_page_size | 0 | | large_pages | OFF | | license | GPL | | local_infile | ON | | locked_in_memory | OFF | | log | OFF | | log_bin | ON | | log_bin_trust_function_creators | OFF | | log_error | /var/log/mysql/mysql-error.log | | log_slave_updates | OFF | | log_slow_queries | OFF | | log_warnings | 1 | | long_query_time | 10 | | low_priority_updates | OFF | | lower_case_file_system | OFF | | lower_case_table_names | 0 | | max_allowed_packet | 1048576 | | max_binlog_cache_size | 18446744073709551615 | | max_binlog_size | 1073741824 | | max_connect_errors | 10 | | max_connections | 500 | | max_delayed_threads | 20 | | max_error_count | 64 | | max_heap_table_size | 16777216 | | max_insert_delayed_threads | 20 | | max_join_size | 18446744073709551615 | | max_length_for_sort_data | 1024 | | max_relay_log_size | 0 | | max_seeks_for_key | 18446744073709551615 | | max_sort_length | 1024 | | max_sp_recursion_depth | 0 | | max_tmp_tables | 32 | | max_user_connections | 0 | | max_write_lock_count | 18446744073709551615 | | multi_range_count | 256 | | myisam_data_pointer_size | 6 | | myisam_max_sort_file_size | 9223372036854775807 | | myisam_recover_options | OFF | | myisam_repair_threads | 1 | | myisam_sort_buffer_size | 8388608 | | myisam_stats_method | nulls_unequal | | net_buffer_length | 16384 | | net_read_timeout | 30 | | net_retry_count | 10 | | net_write_timeout | 60 | | new | OFF | | old_passwords | OFF | | open_files_limit | 2510 | | optimizer_prune_level | 1 | | optimizer_search_depth | 62 | | pid_file | /usr/local/mysql/data/ProductionLinux.pid | | port | 3306 | | preload_buffer_size | 32768 | | protocol_version | 10 | | query_alloc_block_size | 8192 | | query_cache_limit | 1048576 | | query_cache_min_res_unit | 4096 | | query_cache_size | 0 | | query_cache_type | ON | | query_cache_wlock_invalidate | OFF | | query_prealloc_size | 8192 | | range_alloc_block_size | 2048 | | read_buffer_size | 1044480 | | read_only | OFF | | read_rnd_buffer_size | 262144 | | relay_log_purge | ON | | relay_log_space_limit | 0 | | rpl_recovery_rank | 0 | | secure_auth | OFF | | server_id | 71 | | skip_external_locking | ON | | skip_networking | OFF | | skip_show_database | OFF | | slave_compressed_protocol | OFF | | slave_load_tmpdir | /tmp/ | | slave_net_timeout | 3600 | | slave_skip_errors | OFF | | slave_transaction_retries | 10 | | slow_launch_time | 2 | | socket | /tmp/mysql.sock | | sort_buffer_size | 4194296 | | sql_mode | | | sql_notes | ON | | sql_warnings | ON | | storage_engine | MyISAM | | sync_binlog | 0 | | sync_frm | ON | | sync_replication | 0 | | sync_replication_slave_id | 0 | | sync_replication_timeout | 10 | | system_time_zone | CST | | table_cache | 256 | | table_lock_wait_timeout | 50 | | table_type | MyISAM | | thread_cache_size | 30 | | thread_stack | 262144 | | time_format | %H:%i:%s | | time_zone | SYSTEM | | timed_mutexes | OFF | | tmp_table_size | 33554432 | | tmpdir | | | transaction_alloc_block_size | 8192 | | transaction_prealloc_size | 4096 | | tx_isolation | REPEATABLE-READ | | updatable_views_with_limit | YES | | version | 5.0.18-standard-log | | version_comment | MySQL Community Edition - Standard (GPL) | | version_compile_machine | x86_64 | | version_compile_os | unknown-linux-gnu | | wait_timeout | 28800 | +---------------------------------+-----------------------------------------------------------------------------+ 210 rows in set (0.00 sec)
In seiner zweiten sentance gibt er an, dass es eine Quadcore-CPU ist. Mysql 5.0 ist standardmäßig Multithread. – Bastian
Aber wenn Sie nicht für MT codieren, wird es wie ein einzelner Thread funktionieren. – Dani
Dani: 10 gleichzeitige Abfragen sollten über alle CPUs verteilt werden. Sie sollten alle auf einer CPU laufen. Die RDBMS-Engine sollte dies tun: Man codiert nicht für MT auf SQL Server oder Oracle oder Sybase oder andere erwachsene Suchmaschinen – gbn