SYS_RESTORE_LOG
Use SYS_RESTORE_LOG to monitor the migration progress of each table in the cluster during a classic resize to RA3 nodes. It captures the historic throughput of data migration during the resize operation. For more information about classic resize to RA3 nodes, see Classic resize.
SYS_RESTORE_LOG is visible only to superusers.
Table columns
| Column name | Data type | Description |
|---|---|---|
| event_time | timestamp | A timestamp that indicates when the log entry is recorded. |
| database_name | char(128) | The name of the database. |
| schema_name | char(128) | The name of the schema. |
| table_name | char(128) | The name of the table. |
| table_id | integer | The ID of the table. |
| action | char(128) | The action taken at the time of the entry. Values can include: Migration started, checkpoint, resumed, completed, cancelled, or reset. |
| table_size | long | The size of the table. |
| total_data_processed | long | The size of the data in MB processed up to this point for the table. |
| delta_data_processed | long | Size of data processed since the last event_time update, in MB. This helps you determine how much of the data has been processed since the previous recorded time interval. You can compare this with the table_size to get a sense of how quickly data processing is going. |
| message | char(512) | A detailed explanation for the value in the action column. |
| redistribution_type | char(32) | The redistribution type for the table. Either KEY conversion or an EVEN rebalancing task. For more information about distribution styles, see Distribution styles. |
Sample queries
The following query calculates the throughput of data processing, using SYS_RESTORE_LOG.
SELECT ROUND(sum(delta_data_processed) / 1024.0, 2) as data_processed_gb, ROUND(datediff(sec, min(event_time), max(event_time)) / 3600.0, 2) as duration_hr, ROUND(data_processed_gb/duration_hr, 2) as throughput_gb_per_hr from sys_restore_log;
Sample output.
data_processed_gb | duration_hr | throughput_gb_per_hr -------------------+-------------+---------------------- 0.91 | 8.37 | 0.11 (1 row)
The following query that shows all redistribution types.
SELECT * from sys_restore_log ORDER BY event_time;
database_name | schema_name | table_name | table_id | action | total_data_processed | delta_data_processed | event_time | table_size | message | redistribution_type ---------------+----------------------+----------------------+----------+-----------------------------+----------------------+----------------------+----------------------------+------------+---------+-------------------------- dev | schemaaaa877096d844d | customer_key | 106424 | Redistribution started | 0 | | 2024-01-05 02:18:00.744977 | 325 | | Restore Distkey Table dev | schemaaaa877096d844d | dp30907_t2_autokey | 106430 | Redistribution started | 0 | | 2024-01-05 02:18:02.756675 | 90 | | Restore Distkey Table dev | schemaaaa877096d844d | dp30907_t2_autokey | 106430 | Redistribution completed | 90 | 90 | 2024-01-05 02:23:30.643718 | 90 | | Restore Distkey Table dev | schemaaaa877096d844d | customer_key | 106424 | Redistribution completed | 325 | 325 | 2024-01-05 02:23:45.998249 | 325 | | Restore Distkey Table dev | schemaaaa877096d844d | dp30907_t1_even | 106428 | Redistribution started | 0 | | 2024-01-05 02:23:46.083849 | 30 | | Rebalance Disteven Table dev | schemaaaa877096d844d | dp30907_t5_auto_even | 106436 | Redistribution started | 0 | | 2024-01-05 02:23:46.855728 | 45 | | Rebalance Disteven Table dev | schemaaaa877096d844d | dp30907_t5_auto_even | 106436 | Redistribution completed | 45 | 45 | 2024-01-05 02:24:16.343029 | 45 | | Rebalance Disteven Table dev | schemaaaa877096d844d | dp30907_t1_even | 106428 | Redistribution completed | 30 | 30 | 2024-01-05 02:24:20.584703 | 30 | | Rebalance Disteven Table dev | schemaefd028a2a48a4c | customer_even | 130512 | Redistribution started | 0 | | 2024-01-05 04:54:55.641741 | 190 | | Restore Disteven Table dev | schemaefd028a2a48a4c | customer_even | 130512 | Redistribution checkpointed | 29.4342113157737 | 29.4342113157737 | 2024-01-05 04:55:04.770696 | 190 | | Restore Disteven Table (8 rows)