MySQL 5.7 Release Notes
The disk_write_speed_aggregate table provides
aggregated information about the speed of disk writes during
LCP, backup, and restore operations.
The following table provides information about the columns in
the disk_write_speed_aggregate table. For
each column, the table shows the name, data type, and a brief
description. Additional information can be found in the notes
following the table.
Table 21.387 Columns in the disk_write_speed_aggregate table
| Column Name | Type | Description |
|---|---|---|
| node_id | integer | Node ID of this node |
| thr_no | integer | Thread ID of this LDM thread |
| backup_lcp_speed_last_sec | integer | Number of bytes written to disk by backup and LCP processes in the last second |
| redo_speed_last_sec | integer | Number of bytes written to REDO log in the last second |
| backup_lcp_speed_last_10sec | integer | Number of bytes written to disk by backup and LCP processes per second, averaged over the last 10 seconds |
| redo_speed_last_10sec | integer | Number of bytes written to REDO log per second, averaged over the last 10 seconds |
| std_dev_backup_lcp_speed_last_10sec | integer | Standard deviation in number of bytes written to disk by backup and LCP processes per second, averaged over the last 10 seconds |
| std_dev_redo_speed_last_10sec | integer | Standard deviation in number of bytes written to REDO log per second, averaged over the last 10 seconds |
| backup_lcp_speed_last_60sec | integer | Number of bytes written to disk by backup and LCP processes per second, averaged over the last 60 seconds |
| redo_speed_last_60sec | integer | Number of bytes written to REDO log per second, averaged over the last 10 seconds |
| std_dev_backup_lcp_speed_last_60sec | integer | Standard deviation in number of bytes written to disk by backup and LCP processes per second, averaged over the last 60 seconds |
| std_dev_redo_speed_last_60sec | integer | Standard deviation in number of bytes written to REDO log per second, averaged over the last 60 seconds |
| slowdowns_due_to_io_lag | integer | Number of seconds since last node start that disk writes were slowed due to REDO log I/O lag |
| slowdowns_due_to_high_cpu | integer | Number of seconds since last node start that disk writes were slowed due to high CPU usage |
| disk_write_speed_set_to_min | integer | Number of seconds since last node start that disk write speed was set to minimum |
| current_target_disk_write_speed | integer | Actual speed of disk writes per LDM thread (aggregated) |