config.toml.example

# TiDB Configuration.

# TiDB server host.
host = "0.0.0.0"

# tidb server advertise IP.
advertise-address = ""

# TiDB server port.
port = 4000

# Registered store name, [tikv, mocktikv, unistore]
store = "unistore"

# TiDB storage path.
path = "/tmp/tidb"

# The socket file to use for connection.
socket = ""

# Run ddl worker on this tidb-server.
run-ddl = true

# Schema lease duration, very dangerous to change only if you know what you do.
lease = "45s"

# When create table, split a separated region for it. It is recommended to
# turn off this option if there will be a large number of tables created.
split-table = true

# The limit of concurrent executed sessions.
token-limit = 1000

# The maximum memory available for a single SQL statement. Default: 1GB
mem-quota-query = 1073741824

# Controls whether to enable the temporary storage for some operators when a single SQL statement exceeds the memory quota specified by mem-quota-query.
oom-use-tmp-storage = true

# Specifies the temporary storage path for some operators when a single SQL statement exceeds the memory quota specified by mem-quota-query.
# It defaults to a generated directory in `<TMPDIR>/<os/user.Current().Uid>_tidb/` if it is unset.
# It only takes effect when `oom-use-tmp-storage` is `true`.
# tmp-storage-path = "/tmp/<os/user.Current().Uid>_tidb/MC4wLjAuMDo0MDAwLzAuMC4wLjA6MTAwODA=/tmp-storage"

# Specifies the maximum use of temporary storage (bytes) for all active queries when `oom-use-tmp-storage` is enabled.
# If the `tmp-storage-quota` exceeds the capacity of the temporary storage directory, tidb-server would return an error and exit.
# The default value of tmp-storage-quota is under 0 which means tidb-server wouldn't check the capacity.
tmp-storage-quota = -1

# Specifies what operation TiDB performs when a single SQL statement exceeds the memory quota specified by mem-quota-query and cannot be spilled over to disk.
# Valid options: ["log", "cancel"]
oom-action = "cancel"

# Enable batch commit for the DMLs.
enable-batch-dml = false

# Set system variable 'lower_case_table_names'
lower-case-table-names = 2

# Make "kill query" behavior compatible with MySQL. It's not recommend to
# turn on this option when TiDB server is behind a proxy.
compatible-kill-query = false

# Make SIGTERM wait N seconds before starting the shutdown procedure. This is designed for when TiDB is behind a proxy/load balancer.
# The health check will fail immediately but the server will not start shutting down until the time has elapsed.
graceful-wait-before-shutdown = 0

# check mb4 value in utf8 is used to control whether to check the mb4 characters when the charset is utf8.
check-mb4-value-in-utf8 = true

# treat-old-version-utf8-as-utf8mb4 use for upgrade compatibility. Set to true will treat old version table/column UTF8 charset as UTF8MB4.
treat-old-version-utf8-as-utf8mb4 = true

# max-index-length is used to deal with compatibility issues from v3.0.7 and previous version upgrades. It can only be in [3072, 3072*4].
max-index-length = 3072

# index-limit is used to deal with compatibility issues. It can only be in [64, 64*8].
index-limit = 64

# enable-table-lock is used to control table lock feature. Default is false, indicate the table lock feature is disabled.
enable-table-lock = false

# delay-clean-table-lock is used to control the time (Milliseconds) of delay before unlock the table in the abnormal situation.
delay-clean-table-lock = 0

# Maximum number of the splitting region, which is used by the split region statement.
split-region-max-num = 1000

# alter-primary-key is used to control whether the primary keys are clustered. 
# Note that this config is deprecated. Only valid when @@global.tidb_enable_clustered_index = 'int_only'.
# Default is false, only the integer primary keys are clustered.
# If it is true, all types of primary keys are nonclustered.
alter-primary-key = false

# server-version is used to change the version string of TiDB in the following scenarios:
# 1. the server version returned by builtin-function `VERSION()`.
# 2. the server version filled in handshake packets of MySQL Connection Protocol, see https://dev.mysql.com/doc/internals/en/connection-phase-packets.html#packet-Protocol::Handshake for more details.
# if server-version = "", the default value(original TiDB version string) is used.
server-version = ""

# repair mode is used to repair the broken table meta in TiKV in extreme cases.
repair-mode = false

# Repair table list is used to list the tables in repair mode with the format like ["db.table",].
# In repair mode, repairing table which is not in repair list will get wrong database or wrong table error.
repair-table-list = []

# The maximum permitted number of simultaneous client connections. When the value is 0, the number of connections is unlimited.
max-server-connections = 0

# Whether new collations are enabled, as indicated by its name, this configuration entry take effect ONLY when a TiDB cluster bootstraps for the first time.
new_collations_enabled_on_first_bootstrap = false

# Don't register information of this TiDB to etcd, so this instance of TiDB won't appear in the services like dashboard.
# This option is useful when you want to embed TiDB into your service(i.e. use TiDB as a library).
# *If you want to start a TiDB service, NEVER enable this.*
skip-register-to-dashboard = false

# When enabled, usage data (for example, instance versions) will be reported to PingCAP periodically for user experience analytics.
# If this config is set to `false` on all TiDB servers, telemetry will be always disabled regardless of the value of the global variable `tidb_enable_telemetry`.
# See PingCAP privacy policy for details: https://pingcap.com/en/privacy-policy/
enable-telemetry = true

# deprecate-integer-display-length is used to be compatible with MySQL 8.0 in which the integer declared with display length will be returned with
# a warning like `Integer display width is deprecated and will be removed in a future release`.
deprecate-integer-display-length = false

# enable-enum-length-limit is used to deal with compatibility issues. When true, the enum/set element length is limited.
# According to MySQL 8.0 Refman:
# The maximum supported length of an individual SET element is M <= 255 and (M x w) <= 1020,
# where M is the element literal length and w is the number of bytes required for the maximum-length character in the character set.
# See https://dev.mysql.com/doc/refman/8.0/en/string-type-syntax.html for more details.
enable-enum-length-limit = true

[log]
# Log level: debug, info, warn, error, fatal.
level = "info"

# Log format, one of json or text.
format = "text"

# Enable automatic timestamps in log output, if not set, it will be defaulted to true.
# enable-timestamp = true

# Enable annotating logs with the full stack error message, if not set, it will be defaulted to false.
# enable-error-stack = false

# Whether to enable slow query log.
enable-slow-log = true

# Stores slow query log into separated files.
slow-query-file = "tidb-slow.log"

# Queries with execution time greater than this value will be logged. (Milliseconds)
slow-threshold = 300

# record-plan-in-slow-log is used to enable record query plan in slow log.
# 0 is disable. 1 is enable.
record-plan-in-slow-log = 1

# Queries with internal result greater than this value will be logged.
expensive-threshold = 10000

# Maximum query length recorded in log.
query-log-max-len = 4096

# File logging.
[log.file]
# Log file name.
filename = ""

# Max log file size in MB (upper limit to 4096MB).
max-size = 300

# Max log file keep days. No clean up by default.
max-days = 0

# Maximum number of old log files to retain. No clean up by default.
max-backups = 0

[security]
# Path of file that contains list of trusted SSL CAs for connection with mysql client.
ssl-ca = ""

# Path of file that contains X509 certificate in PEM format for connection with mysql client.
ssl-cert = ""

# Path of file that contains X509 key in PEM format for connection with mysql client.
ssl-key = ""

# Path of file that contains list of trusted SSL CAs for connection with cluster components.
cluster-ssl-ca = ""

# Path of file that contains X509 certificate in PEM format for connection with cluster components.
cluster-ssl-cert = ""

# Path of file that contains X509 key in PEM format for connection with cluster components.
cluster-ssl-key = ""

# Configurations of the encryption method to use for encrypting the spilled data files.
# Possible values are "plaintext", "aes128-ctr", if not set, it will be "plaintext" by default.
# "plaintext" means encryption is disabled.
spilled-file-encryption-method = "plaintext"

# Security Enhanced Mode (SEM) restricts the "SUPER" privilege and requires fine-grained privileges instead.
enable-sem = false

# Automatic creation of TLS certificates
auto-tls = true

# Minium TLS version to use, e.g. "TLSv1.2"
tls-version = ""

# The RSA Key size for automatic generated RSA keys
rsa-key-size = 4096

[status]
# If enable status report HTTP service.
report-status = true

# TiDB status host.
status-host = "0.0.0.0"

## status-host is the HTTP address for reporting the internal status of a TiDB server, for example:
## API for prometheus: http://${status-host}:${status_port}/metrics
## API for pprof:      http://${status-host}:${status_port}/debug/pprof
# TiDB status port.
status-port = 10080

# Prometheus pushgateway address, leaves it empty will disable push to pushgateway.
metrics-addr = ""

# Prometheus client push interval in second, set \"0\" to disable push to pushgateway.
metrics-interval = 15

# Record statements qps by database name if it is enabled.
record-db-qps = false

[performance]
# Max CPUs to use, 0 use number of CPUs in the machine.
max-procs = 0

# Memory size quota for tidb server, 0 means unlimited
server-memory-quota = 0

# The alarm threshold when memory usage of the tidb-server exceeds. The valid value range is greater than or equal to 0
# and less than or equal to 1. The default value is 0.8.
# If this configuration is set to 0 or 1, it'll disable the alarm.
# Otherwise, related information will be recorded in the directory `tmp-storage-path/record`.
# Note: If the configuration `server-memory-quota` is set and larger than 0, the alarm threshold will be
# `memory-usage-alarm-ratio * server-memory-quota`; otherwise, it'll be `memory-usage-alarm-ratio * system memory size`.
memory-usage-alarm-ratio = 0.8

# StmtCountLimit limits the max count of statement inside a transaction.
stmt-count-limit = 5000

# Set keep alive option for tcp connection.
tcp-keep-alive = true

# Whether support cartesian product.
cross-join = true

# Stats lease duration, which influences the time of analyze and stats load.
stats-lease = "3s"

# Run auto analyze worker on this tidb-server.
run-auto-analyze = true

# Probability to use the query feedback to update stats, 0.0 or 1.0 for always false/true.
feedback-probability = 0.0

# The max number of query feedback that cache in memory.
query-feedback-limit = 512

# Pseudo stats will be used if the ratio between the modify count and
# row count in statistics of a table is greater than it.
pseudo-estimate-ratio = 0.8

# Force the priority of all statements in a specified priority.
# The value could be "NO_PRIORITY", "LOW_PRIORITY", "HIGH_PRIORITY" or "DELAYED".
force-priority = "NO_PRIORITY"

# Bind info lease duration, which influences the duration of loading bind info and handling invalid bind.
bind-info-lease = "3s"

# Whether support pushing down aggregation with distinct to cop task
distinct-agg-push-down = false

# The limitation of the size in byte for the entries in one transaction.
# If using TiKV as the storage, the entry represents a key/value pair.
# NOTE: If binlog is enabled with Kafka (e.g. arbiter cluster),
# this value should be less than 1073741824(1G) because this is the maximum size that can be handled by Kafka.
# If binlog is disabled or binlog is enabled without Kafka, this value should be less than 10737418240(10G).
txn-total-size-limit = 104857600

# The limitation of the size in byte for each entry in one transaction.
# NOTE: Increasing this limit may cause performance problems.
txn-entry-size-limit = 6291456

# The max number of running concurrency two phase committer request for an SQL.
committer-concurrency = 128

# max lifetime of transaction ttl manager.
max-txn-ttl = 3600000

# the interval duration between two memory profile into global tracker
mem-profile-interval = "1m"

# The Go GC trigger factor, you can get more information about it at https://golang.org/pkg/runtime.
# If you encounter OOM when executing large query, you can decrease this value to trigger GC earlier.
# If you find the CPU used by GC is too high or GC is too frequent and impact your business you can increase this value.
gogc = 100

[proxy-protocol]
# PROXY protocol acceptable client networks.
# Empty string means disable PROXY protocol, * means all networks.
networks = ""

# PROXY protocol header read timeout, unit is second
header-timeout = 5

[prepared-plan-cache]
enabled = false
capacity = 100
memory-guard-ratio = 0.1

[opentracing]
# Enable opentracing.
enable = false

# Whether to enable the rpc metrics.
rpc-metrics = false

[opentracing.sampler]
# Type specifies the type of the sampler: const, probabilistic, rateLimiting, or remote
type = "const"

# Param is a value passed to the sampler.
# Valid values for Param field are:
# - for "const" sampler, 0 or 1 for always false/true respectively
# - for "probabilistic" sampler, a probability between 0 and 1
# - for "rateLimiting" sampler, the number of spans per second
# - for "remote" sampler, param is the same as for "probabilistic"
# and indicates the initial sampling rate before the actual one
# is received from the mothership
param = 1.0

# SamplingServerURL is the address of jaeger-agent's HTTP sampling server
sampling-server-url = ""

# MaxOperations is the maximum number of operations that the sampler
# will keep track of. If an operation is not tracked, a default probabilistic
# sampler will be used rather than the per operation specific sampler.
max-operations = 0

# SamplingRefreshInterval controls how often the remotely controlled sampler will poll
# jaeger-agent for the appropriate sampling strategy.
sampling-refresh-interval = 0

[opentracing.reporter]
# QueueSize controls how many spans the reporter can keep in memory before it starts dropping
# new spans. The queue is continuously drained by a background go-routine, as fast as spans
# can be sent out of process.
queue-size = 0

# BufferFlushInterval controls how often the buffer is force-flushed, even if it's not full.
# It is generally not useful, as it only matters for very low traffic services.
buffer-flush-interval = 0

# LogSpans, when true, enables LoggingReporter that runs in parallel with the main reporter
# and logs all submitted spans. Main Configuration.Logger must be initialized in the code
# for this option to have any effect.
log-spans = false

#  LocalAgentHostPort instructs reporter to send spans to jaeger-agent at this address
local-agent-host-port = ""

[pd-client]
# Max time which PD client will wait for the PD server in seconds.
pd-server-timeout = 3

[tikv-client]
# Max gRPC connections that will be established with each tikv-server.
grpc-connection-count = 4

# After a duration of this time in seconds if the client doesn't see any activity it pings
# the server to see if the transport is still alive.
grpc-keepalive-time = 10

# After having pinged for keepalive check, the client waits for a duration of Timeout in seconds
# and if no activity is seen even after that the connection is closed.
grpc-keepalive-timeout = 3

# The compression type for gRPC channel: none or gzip.
grpc-compression-type = "none"

# Max time for commit command, must be twice bigger than raft election timeout.
commit-timeout = "41s"

# Max batch size in gRPC.
max-batch-size = 128
# Overload threshold of TiKV.
overload-threshold = 200
# Max batch wait time in nanosecond to avoid waiting too long. 0 means disable this feature.
max-batch-wait-time = 0
# Batch wait size, to avoid waiting too long.
batch-wait-size = 8

# Enable chunk encoded data for coprocessor requests.
enable-chunk-rpc = true

# If a Region has not been accessed for more than the given duration (in seconds), it
# will be reloaded from the PD.
region-cache-ttl = 600

# store-limit is used to restrain TiDB from sending request to some stores which is up to the limit.
# If a store has been up to the limit, it will return error for the successive request in same store.
# default 0 means shutting off store limit.
store-limit = 0

# store-liveness-timeout is used to control timeout for store liveness after sending request failed.
store-liveness-timeout = "1s"

# ttl-refreshed-txn-size decides whether a transaction should update its lock TTL.
# If the size(in byte) of a transaction is large than `ttl-refreshed-txn-size`, it update the lock TTL during the 2PC.
ttl-refreshed-txn-size = 33554432

# If the number of keys that one prewrite request of one region involves exceed this threshold, it will use `ResolveLock` instead of `ResolveLockLite`.
resolve-lock-lite-threshold = 16

[tikv-client.copr-cache]
# The capacity in MB of the cache. Zero means disable coprocessor cache.
capacity-mb = 1000.0

[binlog]
# enable to write binlog.
# NOTE: If binlog is enabled with Kafka (e.g. arbiter cluster),
# txn-total-size-limit should be less than 1073741824(1G) because this is the maximum size that can be handled by Kafka.
enable = false

# WriteTimeout specifies how long it will wait for writing binlog to pump.
write-timeout = "15s"

# If IgnoreError is true, when writing binlog meets error, TiDB would stop writing binlog,
# but still provide service.
ignore-error = false

# use socket file to write binlog, for compatible with kafka version tidb-binlog.
binlog-socket = ""

# the strategy for sending binlog to pump, value can be "range" or "hash" now.
strategy = "range"

[pessimistic-txn]
# max retry count for a statement in a pessimistic transaction.
max-retry-count = 256

# The max count of deadlock events that will be recorded in the information_schema.deadlocks table.
deadlock-history-capacity = 10

# Whether retryable deadlocks (in-statement deadlocks) are collected to the information_schema.deadlocks table.
deadlock-history-collect-retryable = false

[stmt-summary]
# enable statement summary.
enable = true

# enable statement summary for TiDB internal query, default is false.
enable-internal-query = false

# max number of statements kept in memory.
max-stmt-count = 3000

# max length of displayed normalized sql and sample sql.
max-sql-length = 4096

# the refresh interval of statement summary, it's counted in seconds.
refresh-interval = 1800

# the maximum history size of statement summary.
history-size = 24

# experimental section controls the features that are still experimental: their semantics,
# interfaces are subject to change, using these features in the production environment is not recommended.
[experimental]

# server level isolation read by engines and labels
[isolation-read]
# engines means allow the tidb server read data from which types of engines. options: "tikv", "tiflash", "tidb".
engines = ["tikv", "tiflash", "tidb"]