TIKV_REGION_STATUS

The TIKV_REGION_STATUS table shows some basic information of TiKV Regions via PD's API, like the Region ID, starting and ending key-values, and read and write traffic.

USE information_schema;
DESC tikv_region_status;

+---------------------------+-------------+------+------+---------+-------+
| Field                     | Type        | Null | Key  | Default | Extra |
+---------------------------+-------------+------+------+---------+-------+
| REGION_ID                 | bigint(21)  | YES  |      | NULL    |       |
| START_KEY                 | text        | YES  |      | NULL    |       |
| END_KEY                   | text        | YES  |      | NULL    |       |
| TABLE_ID                  | bigint(21)  | YES  |      | NULL    |       |
| DB_NAME                   | varchar(64) | YES  |      | NULL    |       |
| TABLE_NAME                | varchar(64) | YES  |      | NULL    |       |
| IS_INDEX                  | tinyint(1)  | NO   |      | 0       |       |
| INDEX_ID                  | bigint(21)  | YES  |      | NULL    |       |
| INDEX_NAME                | varchar(64) | YES  |      | NULL    |       |
| EPOCH_CONF_VER            | bigint(21)  | YES  |      | NULL    |       |
| EPOCH_VERSION             | bigint(21)  | YES  |      | NULL    |       |
| WRITTEN_BYTES             | bigint(21)  | YES  |      | NULL    |       |
| READ_BYTES                | bigint(21)  | YES  |      | NULL    |       |
| APPROXIMATE_SIZE          | bigint(21)  | YES  |      | NULL    |       |
| APPROXIMATE_KEYS          | bigint(21)  | YES  |      | NULL    |       |
| REPLICATIONSTATUS_STATE   | varchar(64) | YES  |      | NULL    |       |
| REPLICATIONSTATUS_STATEID | bigint(21)  | YES  |      | NULL    |       |
+---------------------------+-------------+------+------+---------+-------+
17 rows in set (0.00 sec)

The descriptions of the columns in the TIKV_REGION_STATUS table are as follows:

REGION_ID: The ID of the Region.
START_KEY: The value of the start key of the Region.
END_KEY: The value of the end key of the Region.
TABLE_ID: The ID of the table to which the Region belongs.
DB_NAME: The name of the database to which TABLE_ID belongs.
TABLE_NAME: The name of the table to which the Region belongs.
IS_INDEX: Whether the Region data is an index. 0 means that it is not an index, while 1 means that it is an index. If the current Region contains both table data and index data, there will be multiple rows of records, and IS_INDEX is 0 and 1 respectively.
INDEX_ID: The ID of the index to which the Region belongs. If IS_INDEX is 0, the value of this column is NULL.
INDEX_NAME: The name of the index to which the Region belongs. If IS_INDEX is 0, the value of this column is NULL.
EPOCH_CONF_VER: The version number of the Region configuration. The version number increases when a peer is added or removed.
EPOCH_VERSION: The current version number of the Region. The version number increases when the Region is split or merged.
WRITTEN_BYTES: The amount of data (bytes) written to the Region.
READ_BYTES: The amount of data (bytes) that has been read from the Region.
APPROXIMATE_SIZE: The approximate data size (MB) of the Region.
APPROXIMATE_KEYS: The approximate number of keys in the Region.
REPLICATIONSTATUS_STATE: The current replication status of the Region. The status might be UNKNOWN, SIMPLE_MAJORITY, or INTEGRITY_OVER_LABEL.
REPLICATIONSTATUS_STATEID: The identifier corresponding to REPLICATIONSTATUS_STATE.

Also, you can implement the top confver, top read and top write operations in pd-ctl via the ORDER BY X LIMIT Y operation on the EPOCH_CONF_VER, WRITTEN_BYTES and READ_BYTES columns.

You can query the top 3 Regions with the most write data using the following SQL statement:

SELECT * FROM tikv_region_status ORDER BY written_bytes DESC LIMIT 3;