Disk Fragmentation

The Disk Fragmentation check analyzes the fragmentation of a Windows device's local NTFS volumes and raises a warning or critical result when the share of fragmented files reaches your thresholds. It only analyzes; it does not defragment anything. The check runs on Windows only (x64 and Arm64), once a day (every 1440 minutes) by default.

Steps

1. Go to Devices and open the device.
2. Click the Checks tab → Add Check → Disk Fragmentation.
3. Adjust the thresholds if needed and list any volumes the check should skip under Exclude volumes.
4. Click Add Check.

Alternatively, assign the check with a config package.

Settings

If Warning fragmentation (%) is higher than Error fragmentation (%), the check swaps the two values before evaluation.

Results

The check uses the share of fragmented files that the Windows defragmentation analysis reports for the volume.

The overall result is the worst result across all volumes. For each volume the check shows the drive letter (the volume path for volumes without one), the label, the file system, and the fragmentation percentage.

Monitored volumes

• The check includes local disk volumes formatted with NTFS or ReFS, including volumes without a drive letter. It only analyzes fragmentation on NTFS. ReFS volumes appear without a value (n/a) and count as OK.
• If the analysis fails for an individual NTFS volume, that volume also appears without a value and counts as OK.
• The check queries the volumes through PowerShell. The analysis scans the whole volume and can take a while. It has a fixed time limit of 120 seconds.

Platform support

See also: Set up alerts for a check