Select the unit of measurement for the threshold value.

For size-related resource controls, choose from among the following units:
- b: bytes
- kb: kilobytes
- mb: megabytes
- gb: gigabytes
- tb: terabytes

For time-related resource controls, choose from among the following units:
- s: seconds
- ms: milliseconds
- ks: kiloseconds
- Ms: megaseconds
- Gs: gigaseconds

Units of time or size do not apply to the following resource controls.
- project.cpu-shares
- task.max-lwps
- process.max-file-descriptor