Available Disk Space Trigger

The disk-space trigger can be used when a specific job needs to be executed when the amount of available disk space on a given drive or volume drops below or goes above a determined threshold. The parameter field Drive/Volume allows the specification of a drive or volume name. For locally attached drives on the machine, this would be done by providing a valid drive specification such as C:\ or any other valid local drives. Keep in mind of course, that these would be referring to drives local to the machine running the JobServer.NET service. If you are running the JobServer.NET Manager application on a desktop machine connected to a remote service, then you are specifying the drives on the remote machine.

For specifying a volume available on the network, you should use the UNC path convention such as \\MyServer\ShareName to specify any path that is available on the network. Be certain that the proper permissions are available for JobServer.NET otherwise it will not be able to get access to the network volume. The next two parameter fields work in tandem to define the threshold. The first is the Threshold Amount and this should be a whole number value. This is used with the Threshold Type field which specifies if the amount is either a percentage of the size of the disk or volume. If percentage is used for type, then the value should be limited to a setting from 1 to 100. Otherwise, it defines the scale of the value allowing you to specify the amount as being a whole number of Kilobytes (KB), Megabytes (MB), Gigabytes (GB), Terabytes (TB), Petabytes (PB).

The next parameter is the Trigger Threshold which allows you to choose between triggering on the amount of free space being Above or Below the threshold value specified. The value specified for Minutes Between Checks allows you to control how frequently the available space is monitored. The value for Minutes Before Triggering controls the period which the available disk space must remain beyond the detected threshold before the trigger starts the job. Let us use an example where you have a disk-space trigger defined on a drive where processes might be creating temporary work files and they normally remove them once completed. If the amount of available space crosses the threshold while the process is running and you do not want the trigger to start before the process cleans up its temporary files, then the minutes before triggering setting should be increased to a value that is higher than the expected runtime of the process. If not, then it is possible that the trigger will start the job due to the existence of the temporary working files. Thus, be aware of such situations otherwise you may see unintended jobs running without an obvious reason as to why afterwards.

And the last parameter is the Minutes Between Triggers field. This option allows you to control how often the trigger responds to crossing of the defined threshold. Again, if you have other processes that create large enough temporary working files, this option can help you get the desired behavior from the disk-space trigger. The default behavior is the same as setting this to zero. It will trigger on each threshold crossing. Putting a larger value in here can help you filter how frequently you are running jobs when this threshold is being reached on a regular basis.