How to Fix System Logs Taking Up Space in macOS Tahoe 26.2
Are hidden log files consuming tens of gigabytes on your Mac?
Follow Fix 1: The Automated Log Purge — full Terminal commands and step-by-step instructions below. Verified on macOS Tahoe 26.2.
Recommended Troubleshooting Tool
Before proceeding with manual fixes, we recommend using CleanMyMac X. The gold standard for identifying hidden System Data bloat and runaway log files.
The Symptom
Your storage is full, and tools show that /var/log or /private/var/db/diagnostics is massive.
The Fix
- The Terminal Log Flush
Open Terminal and clear the system log databases:
sudo log erase --all
- Delete ASL Logs
sudo rm -rf /var/log/asl/*.asl
- Disable Verbose Logging
If you recently ran a beta or diagnostic tool, ensure you've turned off verbose mode, which can generate gigabytes of text files in minutes.
Fix 3: The Automated Log Purge
When system processes are "chatty" and generating logs faster than you can delete them.
Recommended Tool: CleanMyMac X
- System Junk: Automatically identifies and removes system logs, user logs, and crash reports that are safe to delete.
- Maintenance: Rotates and compresses logs to ensure they don't grow out of control in the future.