Details
If your computer is asleep or turned off, CrashPlan doesn't run and therefore it can't back up or restore files. If you need to back up or restore a large number of files, we recommend (temporarily) disabling your computer's sleep settings. The Code42 article link provided below includes links to information about modifying your computer's energy settings to facilitate uninterrupted backup and restore tasks.
Considerations
Disabling your sleep settings is especially useful if you are completing your initial backup, or restoring your entire system. However, it can be used any time you need the CrashPlan app to back up or restore a large amount of files. This can significantly reduce the time it takes to complete the backup or restore process.
Once the Code42 app is done backing up or downloading your files, you can change the sleep settings back to their original settings.
Article - Optimize energy settings
https://support.code42.com/CrashPlan/6/Get_started/Optimize_energy_settings