mysql有数百个参数，我们不可能每一个都能了解，所以必须有所选择。本文讲述其中对服务器性能影响比较大的参数，解释作用并给出调优原则和建议值。参数可能涉及到mysql原理的方方面面，所以和后面要讲的内容有千丝万缕的联系，所以本文可能会经常修改。

参数模板

以下配置来自于姜承尧的最佳配置模板

# 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

## 部分参数解释

对一些参数做说明（该列表会随着文章撰写不断增长）：