TiDB Binlog Configuration File

This document introduces the configuration items of TiDB Binlog.

Pump

This section introduces the configuration items of Pump. For the example of a complete Pump configuration file, see Pump Configuration.

addr

• Specifies the listening address of HTTP API in the format of host:port.
• Default value: 127.0.0.1:8250

advertise-addr

• Specifies the externally accessible HTTP API address. This address is registered in PD in the format of host:port.
• Default value: 127.0.0.1:8250

socket

• The Unix socket address that HTTP API listens to.
• Default value: ""

pd-urls

• Specifies the comma-separated list of PD URLs. If multiple addresses are specified, when the PD client fails to connect to one address, it automatically tries to connect to another address.
• Default value: http://127.0.0.1:2379

data-dir

• Specifies the directory where binlogs and their indexes are stored locally.
• Default value: data.pump

heartbeat-interval

• Specifies the heartbeat interval (in seconds) at which the latest status is reported to PD.
• Default value: 2

gen-binlog-interval

• Specifies the interval (in seconds) at which data is written into fake binlog.
• Default value: 3

gc

• Specifies the number of days (integer) that binlogs can be stored locally. Binlogs stored longer than the specified number of days are automatically deleted.
• Default value: 7

log-file

• Specifies the path where log files are stored. If the parameter is set to an empty value, log files are not stored.
• Default value: ""

log-level

• Specifies the log level.
• Default value: info

node-id

• Specifies the Pump node ID. With this ID, this Pump process can be identified in the cluster.
• Default value: hostname:port number. For example, node-1:8250.

security

This section introduces configuration items related to security.

ssl-ca

• Specifies the file path of the trusted SSL certificate list or CA list. For example, /path/to/ca.pem.
• Default value: ""

ssl-cert

• Specifies the path of the X509 certificate file encoded in the Privacy Enhanced Mail (PEM) format. For example, /path/to/pump.pem.
• Default value: ""

ssl-key

• Specifies the path of the X509 key file encoded in the PEM format. For example, /path/to/pump-key.pem.
• Default value: ""

storage

This section introduces configuration items related to storage.

sync-log

• Specifies whether to use fsync after each batch write to binlog to ensure data safety.
• Default value: true

kv_chan_cap

• Specifies the number of write requests that the buffer can store before Pump receives these requests.
• Default value: 1048576 (that is, 2 to the power of 20)

slow_write_threshold

• The threshold (in seconds). If it takes longer to write a single binlog file than this specified threshold, the write is considered slow write and "take a long time to write binlog" is output in the log.
• Default value: 1

stop-write-at-available-space

• Binlog write requests is no longer accepted when the available storage space is below this specified value. You can use the format such as 900 MB, 5 GB, and 12 GiB to specify the storage space. If there is more than one Pump node in the cluster, when a Pump node refuses a write request because of the insufficient space, TiDB will automatically write binlogs to other Pump nodes.
• Default value: 10 GiB

kv

Currently the storage of Pump is implemented based on GoLevelDB. Under storage there is also a kv subgroup that is used to adjust the GoLevel configuration. The supported configuration items are shown as below:

• block-cache-capacity
• block-restart-interval
• block-size
• compaction-L0-trigger
• compaction-table-size
• compaction-total-size
• compaction-total-size-multiplier
• write-buffer
• write-L0-pause-trigger
• write-L0-slowdown-trigger

For the detailed description of the above items, see GoLevelDB Document.

Drainer

This section introduces the configuration items of Drainer. For the example of a complete Drainer configuration file, see Drainer Configuration

addr

• Specifies the listening address of HTTP API in the format of host:port.
• Default value: 127.0.0.1:8249

advertise-addr

• Specifies the externally accessible HTTP API address. This address is registered in PD in the format of host:port.
• Default value: 127.0.0.1:8249

log-file

• Specifies the path where log files are stored. If the parameter is set to an empty value, log files are not stored.
• Default value: ""

log-level

• Specifies the log level.
• Default value: info

node-id

• Specifies the Drainer node ID. With this ID, this Drainer process can be identified in the cluster.
• Default value: hostname:port number. For example, node-1:8249.

data-dir

• Specifies the directory used to store files that need to be saved during Drainer operation.
• Default value: data.drainer

detect-interval

• Specifies the interval (in seconds) at which PD updates the Pump information.
• Default value: 5

pd-urls

• The comma-separated list of PD URLs. If multiple addresses are specified, the PD client will automatically attempt to connect to another address if an error occurs when connecting to one address.
• Default value: http://127.0.0.1:2379

initial-commit-ts

• Specifies from which commit timestamp the replication task starts. This configuration is only applicable to the Drainer node that starts replication for the first time. If a checkpoint already exists downstream, the replication will be performed according to the time recorded in the checkpoint.
• Default value: -1. Drainer will get a new timestamp from PD as the starting time.

synced-check-time

• You can access the /status path through the HTTP API to query the status of Drainer replication. synced-check-time specifies how many minutes from the last successful replication is considered as synced, that is, the replication is complete.
• Default value: 5

compressor

• Specifies the compression algorithm used for data transfer between Pump and Drainer. Currently only the gzip algorithm is supported.
• Default value: "", which means no compression.

security

This section introduces configuration items related to security.

ssl-ca

• Specifies the file path of the trusted SSL certificate list or CA list. For example, /path/to/ca.pem.
• Default value: ""

ssl-cert

• Specifies the path of the X509 certificate file encoded in the PEM format. For example, /path/to/drainer.pem.
• Default value: ""

ssl-key

• Specifies the path of the X509 key file encoded in the PEM format. For example, /path/to/pump-key.pem.
• Default value: ""

syncer

The syncer section includes configuration items related to the downstream.

db-type

Currently, the following downstream types are supported:

• mysql
• tidb
• kafka
• file

Default value: mysql

sql-mode

• Specifies the SQL mode when the downstream is the mysql or tidb type. If there is more than one mode, use commas to separate them.
• Default value: ""

ignore-txn-commit-ts

• Specifies the commit timestamp at which the binlog is ignored.
• Default value: []

ignore-schemas

• Specifies the database to be ignored during replication. If there is more than one database to be ignored, use commas to separate them. If all changes in a binlog file are filtered, the whole binlog file is ignored.
• Default value: INFORMATION_SCHEMA,PERFORMANCE_SCHEMA,mysql

ignore-table

Ignores the specified table changes during replication. You can specify multiple tables to be ignored in the toml file. For example:

[[syncer.ignore-table]]
db-name = "test"
tbl-name = "log"

[[syncer.ignore-table]]
db-name = "test"
tbl-name = "audit"

If all changes in a binlog file are filtered, the whole binlog file is ignored.

Default value: []

replicate-do-db

• Specifies the database to be replicated. For example, [db1, db2].
• Default value: []

replicate-do-table

Specifies the table to be replicated. For example:

[[syncer.replicate-do-table]]
db-name ="test"
tbl-name = "log"

[[syncer.replicate-do-table]]
db-name ="test"
tbl-name = "~^a.*"

Default value: []

txn-batch

• When the downstream is the mysql or tidb type, DML operations are executed in different batches. This parameter specifies how many DML operations can be included in each transaction.
• Default value: 20

worker-count

• When the downstream is the mysql or tidb type, DML operations are executed concurrently. This parameter specifies the concurrency numbers of DML operations.
• Default value: 16

disable-dispatch

• Disables the concurrency and forcibly set worker-count to 1.
• Default value: false

safe-mode

If the safe mode is enabled, Drainer modifies the replication updates in the following way:

• Insert is modified to Replace Into
• Update is modified to Delete plus Replace Into

Default value: false

syncer.to

The syncer.to section introduces different types of downstream configuration items according to configuration types.

mysql/tidb

The following configuration items are related to connection to downstream databases:

• host: If this item is not set, TiDB Binlog tries to check the MYSQL_HOST environment variable which is localhost by default.
• port: If this item is not set, TiDB Binlog tries to check the MYSQL_PORT environment variable which is 3306 by default.
• user: If this item is not set, TiDB Binlog tries to check the MYSQL_USER environment variable which is root by default.
• password: If this item is not set, TiDB Binlog tries to check the MYSQL_PSWD environment variable which is "" by default.

file

• dir: Specifies the directory where binlog files are stored. If this item is not set, data-dir is used.

kafka

When the downstream is Kafka, the valid configuration items are as follows:

• zookeeper-addrs
• kafka-addrs
• kafka-version
• kafka-max-messages
• topic-name

syncer.to.checkpoint

This section introduces a configuration item related to syncer.to.checkpoint.

type

• Specifies in what way the replication progress is saved.

• Available options: mysql and tidb.

• Default value: The same as the downstream type. For example, when the downstream is file, the progress is saved in the local file system; when the downstream is mysql, the progress is saved in the downstream database. If you explicitly specify using mysql or tidb to store the progress, make the following configuration:

  • schema: tidb_binlog by default.

    Note:

    When deploying multiple Drainer nodes in the same TiDB cluster, you need to specify a different checkpoint schema for each node. Otherwise, the replication progress of two instances will overwrite each other.

  • host

  • user

  • password

  • port