SHOW REBALANCE ALL DATABASES STATUS

Warning

SingleStore 9.0 gives you the opportunity to preview, evaluate, and provide feedback on new and upcoming features prior to their general availability. In the interim, SingleStore 8.9 is recommended for production workloads, which can later be upgraded to SingleStore 9.0.

Syntax

SQL

SHOW REBALANCE ALL DATABASES STATUS;

Remarks

Alternatively, you can query the information schema view MV_REBALANCE_STATUS , which returns the same output as the SHOW REBALANCE ALL DATABASES STATUS command.

The Ordinal is the target partition’s ordinal, and the Target_Host and Target_Port correspond to the destination leaf. Any two operations in the same Phase can be run in parallel and phases are run in order. For example, the aggregator can run COPY PARTITION on partitions test:1 and test:3 in parallel. The exact meaning of what each phase means is arbitrary and depends on the particular rebalance operation. The Estimated_Time_Remaining_Ms is the estimated total time (in milliseconds) that each low-level command will take to complete.

Example

Run the following command to rebalance partitions on all databases in the cluster:

SQL

REBALANCE ALL DATABASES;

View the status of REBALANCE ALL DATABASES while it is still running:

SQL

SHOW REBALANCE ALL DATABASES STATUS;

+----------+-----------------------------------+---------+-------------+-------------+-------+-----------+--------------+-----------------------------+
| Database | Action                            | Ordinal | Target_Host | Target_Port | Phase | Status    | Running_Time | Estimated_Time_Remaining_Ms |
+----------+-----------------------------------+---------+-------------+-------------+-------+-----------+--------------+-----------------------------+
| x_db     | COPY PARTITION                    | 13      | 127.0.0.1   | 10002       | 3     | success   | 4009         | 0                           |
| x_db     | COPY PARTITION                    | 2       | 127.0.0.1   | 10003       | 4     | success   | 5109         | 0                           |
| x_db     | COPY PARTITION                    | 2       | 127.0.0.1   | 10004       | 4     | success   | 5112         | 0                           |
| x_db     | PROMOTE PARTITION WITH DROP FORCE | 2       | 127.0.0.1   | 10003       | 5     | running   | 405          | 1130                        |
| x_db     | DROP PARTITION                    | 2       | 127.0.0.1   | 10002       | 6     | scheduled | NULL         | 1002                        |
| x_db     | DROP PARTITION                    | 13      | 127.0.0.1   | 10004       | 6     | scheduled | NULL         | 1002                        |
+----------+-----------------------------------+---------+-------------+-------------+-------+-----------+--------------+-----------------------------+

Note: The Status displays success for the activities that are already complete. The Estimated_Time_Remaining_Ms displays the estimated remaining time (in milliseconds) for each low-level command to complete.