EXAMPLE : my.cnf mysql configuration file

The MySQL configuration is as follows:
[mysqld]
core-file
user = mysql
port = 3306
datadir = /db
socket = /tmp/mysql.sock
default-storage-engine = innodb
skip-external-locking
log_warnings=1
skip_name_resolve
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
group_concat_max_len = 1000000

server-id = 666

# InnoDB settings
innodb_data_home_dir = /db
innodb_log_group_home_dir = /db
innodb_data_file_path = ibdata1:100M:autoextend
innodb_buffer_pool_size = 20G
innodb_buffer_pool_instances = 8
innodb_log_file_size = 10G
innodb_buffer_pool_load_at_startup=OFF
innodb_buffer_pool_dump_at_shutdown=OFF
# allows for row_format=compressed
innodb_file_format=Barracuda
innodb_log_buffer_size = 64M
innodb_flush_log_at_trx_commit = 0
innodb_lock_wait_timeout = 50
innodb_file_per_table
innodb_doublewrite = 0
innodb_io_capacity = 1200
innodb_read_io_threads = 6
innodb_write_io_threads = 6
innodb_stats_on_metadata = OFF

# Slow query log settings
# The default logs all full table scans,tmp tables,filesorts on disk queries
#use_global_long_query_time = 1
#long_query_time = 0.5
slow_query_log_file = slowquery.log
slow_query_log = 1
long_query_time = 3
log_slow_filter = "full_scan,tmp_table_on_disk,filesort_on_disk"
log_slow_verbosity = "full"

# Other general MySQL settings
sync_binlog = 0
query_cache_type = 0
query_cache_size = 0
max_connections = 3000
thread_cache_size = 1000
back_log = 1024
thread_concurrency = 32
innodb_thread_concurrency = 64
tmpdir = /var/tmp
max_allowed_packet = 24M
max_join_size = 4294967295
net_buffer_length = 2K
thread_stack = 512K
tmp_table_size = 64M
max_heap_table_size = 64M
table_open_cache = 2000

# Replication settings (master to slave)
binlog_cache_size = 2M
binlog_format=mixed
log-bin = bin
log-error = error.log
expire_logs_days = 5
slave-parallel-workers = 10
master-info-repository = "table"
relay-log-info-repository = "table"
gtid_mode = ON
enforce_gtid_consistency = true
log-slave-updates
replicate-ignore-table = mysql.user
replicate-ignore-table = mysql.db
replicate-ignore-table = mysql.tables_priv
replicate-ignore-table = mysql.proxies_priv

# Started tuning slave catchup speed, can use more research
slave-checkpoint-period = 1000
slave-checkpoint-group = 2048