mysql有數(shù)百個(gè)參數(shù),我們不可能每一個(gè)都能了解,所以必須有所選擇。本文講述其中對(duì)服務(wù)器性能影響比較大的參數(shù),解釋作用并給出調(diào)優(yōu)原則和建議值。參數(shù)可能涉及到mysql原理的方方面面,所以和后面要講的內(nèi)容有千絲萬縷的聯(lián)系,所以本文可能會(huì)經(jīng)常修改。
參數(shù)模板
以下配置來自于姜承堯的最佳配置模板
# author: jiangchengyao@gmail.com
[client]
user = root
password = 1111aaA_
[mysql]
prompt = [\\u@\\p][\\d]>\\_
no-auto-rehash
[mysqld_safe]
malloc-lib=tcmalloc
[mysqldump]
single-transaction
[mysqld]
# basic settings #
user = mysql
sql_mode = "STRICT_TRANS_TABLES,NO_ENGINE_SUBSTITUTION,NO_ZERO_DATE,NO_ZERO_IN_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER"
autocommit = 1
server-id = 8888
character_set_server=utf8mb4
datadir=/mysql_data/data
transaction_isolation = READ-COMMITTED
explicit_defaults_for_timestamp = 1
max_allowed_packet = 64M
event_scheduler = 1
# connection #
interactive_timeout = 1800
wait_timeout = 1800
lock_wait_timeout = 1800
skip_name_resolve = 1
max_connections = 1024
max_user_connections = 256
max_connect_errors = 1000000
# table cache performance settings
table_open_cache = 4096
table_definition_cache = 4096
table_open_cache_instances = 64
# session memory settings #
read_buffer_size = 16M
read_rnd_buffer_size = 32M
sort_buffer_size = 32M
tmp_table_size = 64M
join_buffer_size = 128M
thread_cache_size = 64
# log settings #
log_error = error.log
log_bin = binlog
log_error_verbosity = 2
general_log_file = general.log
slow_query_log = 1
slow_query_log_file = slow.log
log_queries_not_using_indexes = 1
log_slow_admin_statements = 1
log_slow_slave_statements = 1
log_throttle_queries_not_using_indexes = 10
expire_logs_days = 90
long_query_time = 2
min_examined_row_limit = 100
log-bin-trust-function-creators = 1
log-slave-updates = 1
# innodb settings #
innodb_page_size = 16384
innodb_buffer_pool_size = 160G
innodb_buffer_pool_instances = 16
innodb_buffer_pool_load_at_startup = 1
innodb_buffer_pool_dump_at_shutdown = 1
innodb_lru_scan_depth = 4096
innodb_lock_wait_timeout = 5
innodb_io_capacity = 10000
innodb_io_capacity_max = 20000
innodb_flush_method = O_DIRECT
innodb_undo_logs = 128
innodb_undo_tablespaces = 3
innodb_flush_neighbors = 0
innodb_log_file_size = 16G
innodb_log_files_in_group = 2
innodb_log_buffer_size = 64M
innodb_purge_threads = 4
innodb_large_prefix = 1
innodb_thread_concurrency = 32
innodb_print_all_deadlocks = 1
innodb_strict_mode = 1
innodb_sort_buffer_size = 64M
innodb_write_io_threads = 16
innodb_read_io_threads = 16
innodb_file_per_table = 1
innodb_stats_persistent_sample_pages = 64
innodb_autoinc_lock_mode = 2
innodb_online_alter_log_max_size=1G
innodb_open_files=4096
# replication settings #
master_info_repository = TABLE
relay_log_info_repository = TABLE
sync_binlog = 1
gtid_mode = on
enforce_gtid_consistency = 1
log_slave_updates
binlog_format = ROW
binlog_rows_query_log_events = 1
relay_log = relay.log
relay_log_recovery = 1
slave_skip_errors = ddl_exist_errors
slave-rows-search-algorithms = 'INDEX_SCAN,HASH_SCAN'
# semi sync replication settings #
plugin-load = "group_replication.so;validate_password.so;semisync_master.so;semisync_slave.so"
loose_rpl_semi_sync_master_enabled = 1
loose_rpl_semi_sync_master_timeout = 3000
loose_rpl_semi_sync_slave_enabled = 1
# password plugin #
validate_password_policy = STRONG
validate-password = FORCE_PLUS_PERMANENT
# perforamnce_schema settings
performance-schema-instrument='memory/%=COUNTED'
performance_schema_digests_size = 40000
performance_schema_max_table_handles = 40000
performance_schema_max_table_instances = 40000
performance_schema_max_sql_text_length = 4096
performance_schema_max_digest_length = 4096
[mysqld-5.6]
# metalock performance settings
metadata_locks_hash_instances = 64
[mysqld-5.7]
# new innodb settings #
loose_innodb_numa_interleave = 1
innodb_buffer_pool_dump_pct = 40
innodb_page_cleaners = 16
innodb_undo_log_truncate = 1
innodb_max_undo_log_size = 2G
innodb_purge_rseg_truncate_frequency = 128
# new replication settings #
slave-parallel-type = LOGICAL_CLOCK
slave-parallel-workers = 16
slave_preserve_commit_order = 1
slave_transaction_retries = 128
# other change settings #
binlog_gtid_simple_recovery = 1
log_timestamps = system
show_compatibility_56 = on
# group replication settings
plugin-load = "group_replication.so;validate_password.so;semisync_master.so;semisync_slave.so"
transaction-write-set-extraction = XXHASH64
# report_host = 127.0.0.1 # optional for group replication
# binlog_checksum = NONE # only for group replication
loose_group_replication = FORCE_PLUS_PERMANENT
loose_group_replication_group_name = "aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa"
loose_group_replication_compression_threshold = 100
loose_group_replication_flow_control_mode = 0
loose_group_replication_single_primary_mode = 0
loose_group_replication_enforce_update_everywhere_checks = 1
loose_group_replication_transaction_size_limit = 10485760
loose_group_replication_unreachable_majority_timeout = 120
loose_group_replication_start_on_boot = 0
## 部分參數(shù)解釋
對(duì)一些參數(shù)做說明(該列表會(huì)隨著文章撰寫不斷增長):
序號(hào) | 參數(shù) | 說明 |
---|---|---|
1 | user =root password = 1111aaA_ | 在my.cnf中寫入用戶名和密碼,無需在登錄框中輸入 |
2 | prompt = [\u@\p][\d]>\_ | 修改提示符為用戶名@時(shí)間、數(shù)據(jù)庫的形式 參考mysql客戶端的使用方法 |
3 | no-auto-rehash | 避免使用mysql自帶的命令提示,因?yàn)椴缓糜谩?br>參考mysql命令提示工具 |
4 | malloc-lib=tcmalloc | 定制內(nèi)存分配庫,替代標(biāo)準(zhǔn)的glibc的malloc, 據(jù)說能提高數(shù)倍的內(nèi)存分配和釋放的性能。 參考文章TCMalloc:線程緩存的Malloc |
5 | single-transaction | 在mysqldump中指定single-transaction時(shí), 使用可重復(fù)讀隔離級(jí)別來保證整個(gè)dump過程中數(shù)據(jù)一致性, 該選項(xiàng)僅對(duì)InnoDB表有用,且不能與DDL操作并行, 參考mysqldump命令之single-transaction |