Understanding file count and storage size discrepancies

Overview

If you compare the folder information on your computer to the information reported in CrashPlan you may notice a difference in the number of files or the total storage size. This is normal behavior. This article explains the common reasons behind these discrepancies.

File count differences

• More files in CrashPlan: Every computer contains hidden files that don't display by default when browsing your system (examples include .DS_Store and desktop.ini). The CrashPlan may detect these files and back them up. The combined total of normal files and hidden files is what you see reported in CrashPlan, which is why CrashPlan may report more files than your OS displays.
• Fewer files in CrashPlan: The CrashPlan app excludes certain non-critical locations and file types (such as system files) from backup by default. Your organization may also have configured exclusions to avoid backing up some files and file types.

Storage size differences

• Smaller size in CrashPlan: The CrashPlan app may report a smaller total data size than your computer for several reasons:
  • Deduplication and compression: Due to deduplication and compression that occurs during the backup process, the CrashPlan app will often show the stored data size as smaller than the original files on your computer.
  • Exclusions: The CrashPlan app excludes certain non-critical locations and file types (such as system files) from backup by default. Your organization may also have configured exclusions to avoid backing up some files and file types.
• Larger size in CrashPlan: The stored size may be larger than the data on your computer because your backup archive includes multiple versions of your files, or deleted files.

• Calculation differences (Base-10 vs. Base-2): Storage can be measured in one of two different ways, which can lead to different values despite the total data being the same.

  What this means
  The CrashPlan app might show your backup being 1.5 GB in size, while the CrashPlan console shows 1.3 GB for the exact same archive. Think of it like the difference between miles and kilometers.

  • Base-10 (megabytes/gigabytes) is used in:
    • CrashPlan app
    • macOS Finder
  • Base-2 (megabytes/gigabytes) is used in:
    • CrashPlan console
    • Windows File Explorer
    • Many Linux file managers

How to verify your backup

While discrepancies are usually not a cause for concern, you can easily verify that all of your files are safely backed up by doing the following:

1. In the CrashPlan app, click Restore files.
2. Navigate to your device’s root folder at the top level of the file tree. Select all drives shown in the list.
3. The CrashPlan app calculates and displays the total size of the selected data, as if you were going to restore it. If the calculated size of the mock restore is close to the total size of your backup file selection, all of your files are backed up.