This option governs the number of completed jobs (and their logs) that are retained by Console: a job is any action that has been completed on any Node instance. The jobs are retained as a historic record. Over time, and especially where there are multiple Applications/Node instances managed in Console, the number of jobs (and their logs) stored by Console can become very large. When this occurs, you may find that it takes a long time for a given Node instance to be fully recognised in Console if the Node instance is restarted for whatever reason - this performance issue is caused by the large number of jobs (and their logs) that are stored by Console and which need to be looped through whenever a Node instance is restarted.
To resolve this issue, you can configure Console to retain a specific number of jobs - i.e. a limit. Enable the option, choose the number of jobs you would like to retain and then click Save, as shown below. In the example below, if there are 200 jobs retained at the time the value is set, then the next time a job is actioned, Console will remove all but 50 of the 200 jobs - i.e. the oldest jobs will be removed. Each time a new job is actioned the oldest job and its logs will be removed to meet the criteria you set.
Setting this option will retain only the specific number of jobs and their logs you choose, therefore, you should use with caution. Any jobs and their logs that do not meet the criteria you set will be deleted the next time a job is run and will no longer be available.