I am new Database engineer. I am having trouble in my server which is using too much CPU on database query(simple count statement). I have googled about it, so i found out it depends on system configuration. So I am posting the same. Here are the following stats of my server:
32 GB Ram
2.7 TB hard drive
150 GB database size(with 2 myisam tables contains billions of record)
mysql version 5.1
Centos
And here's my my.cnf file:
#datadir=/var/lib/mysql
datadir=/home/mysql
socket=/var/lib/mysql/mysql.sock
#socket=/home/mysql/mysql.sock
user=mysql
# Disabling symbolic-links is recommended to prevent assorted security risks
symbolic-links=0
[mysqld_safe]
log-error=/var/log/mysqld.log
pid-file=/var/run/mysqld/mysqld.pid
There is not much details I think my.cnf is not configured according to system configuration.
Please let me know what is the best way I can set parameters in my.cnf so mysql works properly.
Output of Show variable;
SHOW VARIABLES;
| Variable_name | Value |
+-----------------------------------------+-------------------------------------------------------------------------------------------+
| auto_increment_increment | 1 |
| auto_increment_offset | 1 |
| autocommit | ON |
| automatic_sp_privileges | ON |
| back_log | 50 |
| basedir | / |
| big_tables | OFF |
| binlog_cache_size | 32768 |
| binlog_direct_non_transactional_updates | OFF |
| binlog_format | STATEMENT |
| bulk_insert_buffer_size | 8388608 |
| character_sets_dir | /usr/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 | 10 |
| datadir | /home/mysql/ |
| 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 | ON |
| error_count | 0
| event_scheduler | OFF
| expire_logs_days | 0
| flush | OFF
| flush_time | 0
| foreign_key_checks | ON
| general_log | OFF
| general_log_file | /home/mysql/localhost.log |
| group_concat_max_len | 1024
| identity | 0
| ignore_builtin_innodb | OFF
| innodb_adaptive_hash_index | ON
| innodb_additional_mem_pool_size | 1048576
| innodb_autoextend_increment | 8
| innodb_autoinc_lock_mode | 1
| innodb_buffer_pool_size | 8388608
| innodb_checksums | ON
| innodb_commit_concurrency | 0
| innodb_concurrency_tickets | 500
| innodb_data_file_path | ibdata1:10M:autoextend
| 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_buffer_size | 1048576 |
| innodb_log_file_size | 5242880
| innodb_log_files_in_group | 2
| innodb_log_group_home_dir | ./
| innodb_max_dirty_pages_pct | 90
| innodb_max_purge_lag | 0
| innodb_mirrored_log_groups | 1
| innodb_open_files | 300
| innodb_rollback_on_timeout | OFF
| innodb_stats_method | nulls_equal |
| innodb_stats_on_metadata | ON
| innodb_support_xa | ON
| innodb_sync_spin_loops | 20
| innodb_table_locks | ON |
| innodb_thread_concurrency | 8
| innodb_thread_sleep_delay | 10000
| innodb_use_legacy_cardinality_algorithm | ON
| insert_id | 0
| interactive_timeout | 28800
| join_buffer_size | 131072
| keep_files_on_create | OFF
| key_buffer_size | 8384512
| key_cache_age_threshold | 300
| key_cache_block_size | 1024
| key_cache_division_limit | 100
| long_query_time | 10.000000 |
| max_allowed_packet | 1048576 |
| max_binlog_cache_size | 18446744073709547520 |
| max_binlog_size | 1073741824 |
| max_connect_errors | 10 |
| max_connections | 151 |
| 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_long_data_size | 1048576 |
| max_prepared_stmt_count | 16382 |
| 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 |
| min_examined_row_limit | 0 |
| multi_range_count | 256 |
| myisam_data_pointer_size | 6 |
| myisam_max_sort_file_size | 9223372036853727232 |
| myisam_mmap_size | 18446744073709551615 |
| myisam_recover_options | OFF |
| myisam_repair_threads | 1 |
| myisam_sort_buffer_size | 8388608 |
| myisam_stats_method | nulls_unequal |
| myisam_use_mmap | OFF |
| net_buffer_length | 16384 |
| net_read_timeout | 30 |
| net_retry_count | 10 |
| net_write_timeout | 60 |
| open_files_limit | 1024 |
| optimizer_prune_level | 1 |
| optimizer_search_depth | 62 |
| optimizer_switch | index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on |
| pid_file | /home/mysql/localhost.localdomain.pid |
| plugin_dir | /usr/lib64/mysql/plugin |
| port | 3306 |
| preload_buffer_size | 32768 |
| profiling | OFF |
| profiling_history_size | 15 |
| protocol_version | 10 |
| pseudo_thread_id | 18 |
| 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 | 4096 |
| read_buffer_size | 131072 |
| read_only | OFF |
| read_rnd_buffer_size | 262144 |
| rpl_recovery_rank | 0 |
| secure_auth | OFF | |skip_external_locking | ON |
| slow_launch_time | 2 |
| slow_query_log | OFF |
| slow_query_log_file | /home/mysql/localhost-slow.log |
| socket | /var/lib/mysql/mysql.sock |
| sort_buffer_size | 2097144 |
| sql_auto_is_null | ON |
| sql_big_selects | ON |
| sql_big_tables | OFF |
| sql_buffer_result | OFF |
| sql_log_bin | ON |
| sql_log_off | OFF |
| sql_log_update | ON |
| sql_low_priority_updates | OFF |
| sql_max_join_size | 18446744073709551615 |
| sql_mode | |
| sql_notes | ON |
| sql_quote_show_create | ON |
| sql_safe_updates | OFF |
| sql_select_limit | 18446744073709551615 |
| sql_slave_skip_counter | |
| sql_warnings | |
| storage_engine | MyISAM |
| table_definition_cache | 256 |
| table_lock_wait_timeout | 50 |
| table_open_cache | 64 |
| table_type | MyISAM |
| thread_cache_size | 0 |
| thread_handling | one-thread-per-connection |
| thread_stack | 262144 |
|
| timestamp | 1401967364 |
| tmp_table_size | 16777216 |
| tmpdir | /tmp |
| transaction_alloc_block_size | 8192 |
| transaction_prealloc_size | 4096 |
| tx_isolation | REPEATABLE-READ