Aborted clients
Job details
| Name: | Aborted clients |
| Platform: | Mysql |
| Category: | Availability |
| Description: | Checks the number of clients not closing the connection properly. |
| Long description: | Checks the number of clients not closing the connection properly. |
| Version: | 1.1 |
| Default schedule: | 12,42 * * * |
| Requires engine install: | Yes |
| Compatibility tag: | .[type=‘instance’ & is_mysql_branch=‘1′]/.[hasengine=‘YES’ & use_global_variables_information_schema = ‘1′ ] |
Parameters
| Name | Default value | Description |
|---|---|---|
| warning threshold | 50 | The maximum value of aborted clients (over a period of time defined by the [time threshold] parameter) before a warning is triggered. |
| alarm threshold | 500 | The maximum value of aborted clients (over a period of time defined by the [time threshold] parameter) before an alarm is triggered. |
| threshold (time) | 120 | A period of time (in minutes) which must be passed (combined with the number of aborted clients) before an alarm or a warning is returned by the procedure. |
| enable warnings and alarms | NO | If set to “NO” (default), the alert will only collect statistics without returning status warning or alarm. Value “YES“ will activate the alert. |
| history threshold | 7 | The maximum number of day to kept statistics for in the historic tables. |
Job Summary
- Purpose: The purpose of the “Aborted clients” job is to monitor the number of clients that are not closing the connection to the MySQL database properly. This condition might affect the stability and performance of the database.
- Why: It is important to track these occurrences to prevent server crashes and avoid potential data loss. Constant open connections in MySQL could consume substantial server resources. Over time this can lead to server overload and subsequent crashes. The monitoring job allows these conditions to be detected and alerted upon early, allowing administrators to address the issue before it escalates.
- Manual checking: You can manually check the number of aborted clients in MySQL by running the following SQL command:
SELECT cast(VARIABLE_VALUE as signed) FROM information_schema.global_status WHERE variable_name = 'Aborted_clients'Alerts and Reports
This job is capable of triggering alerts upon reaching predefined warning and alarm thresholds of aborted clients. Additionally, the job maintains a historical table of aborted clients, enabling analysis of trends over time. This information can be useful for identifying patterns and implementing preventive measures. The monitoring job also includes a report showing the history of aborted clients which are displayed on a graph.
Dependencies and Implementation
The monitoring job has several dependencies including stored procedures and tables needed for its operation. These dependencies will be cleaned up (dropped) in case of any failure while running the job.
The job creates and updates two tables (“dbw_aborted_clients_histr” and “dbw_aborted_clients_last”) to store the information about the aborted clients. The job also creates a stored procedure (“dbw_aborted_clients”) to gather this data, analyze it against the defined thresholds, and trigger alerts if necessary.
Installation and Compatibility
The job is intended for automatic installation and is compatible with MySQL databases that support the use of global variables and the information schema.