Submodule box.cfg
The box.cfg submodule is used for specifying server configuration parameters.
To view the current configuration, say box.cfg without braces:
tarantool> box.cfg --- - checkpoint_count: 2 too_long_threshold: 0.5 slab_alloc_factor: 1.05 memtx_max_tuple_size: 1048576 background: false <...> ... To set particular parameters, use the following syntax: box.cfg{key = value [, key = value ...]} (further referred to as box.cfg{...} for short). For example:
tarantool> box.cfg{listen = 3301} Parameters that are not specified in the box.cfg{...} call explicitly will be set to the default values.
If you say box.cfg{} with no parameters, Tarantool applies the following default settings to all the parameters:
tarantool> box.cfg{} tarantool> box.cfg -- sorted in the alphabetic order --- - background = false checkpoint_count = 2 checkpoint_interval = 3600 checkpoint_wal_threshold = 1000000000000000000 coredump = false custom_proc_title = nil feedback_enabled = true feedback_host = 'https://feedback.tarantool.io' feedback_interval = 3600 force_recovery = false hot_standby = false instance_uuid = nil -- generated automatically io_collect_interval = nil iproto_threads = 1 listen = nil log = nil log_format = plain log_level = 5 log_nonblock = true memtx_dir = '.' memtx_max_tuple_size = 1024 * 1024 memtx_memory = 256 * 1024 *1024 memtx_min_tuple_size = 16 net_msg_max = 768 pid_file = nil readahead = 16320 read_only = false replicaset_uuid = nil -- generated automatically replication = nil replication_anon = false replication_connect_timeout = 30 replication_skip_conflict = false replication_sync_lag = 10 replication_sync_timeout = 0 replication_timeout = 1 slab_alloc_factor = 1.05 snap_io_rate_limit = nil sql_cache_size = 5242880 strip_core = true too_long_threshold = 0.5 username = nil vinyl_bloom_fpr = 0.05 vinyl_cache = 128 * 1024 * 1024 vinyl_dir = '.' vinyl_max_tuple_size = 1024 * 1024* 1024 * 1024 vinyl_memory = 128 * 1024 * 1024 vinyl_page_size = 8 * 1024 vinyl_range_size = nil vinyl_read_threads = 1 vinyl_run_count_per_level = 2 vinyl_run_size_ratio = 3.5 vinyl_timeout = 60 vinyl_write_threads = 4 wal_dir = '.' wal_dir_rescan_delay = 2 wal_max_size = 256 * 1024 * 1024 wal_mode = 'write' worker_pool_threads = 4 work_dir = nil The first call to box.cfg{...} (with or without parameters) initiates Tarantool’s database module box.
box.cfg{...} is also the command that reloads persistent data files into RAM upon restart once we have data.