The Proactive Assistant
In modern versions of macOS, the operating system attempts to be highly proactive. When you receive an email discussing a flight itinerary, macOS will automatically highlight the flight number and suggest adding it to your Calendar. If a colleague texts you an address in Messages, macOS will suggest pulling up a map. This underlying intelligence is powered by the Core Suggestions framework.
To ensure these suggestions appear instantly without scanning your hard drive in real-time, the Core Suggestions daemon (suggestd) constantly parses your communications in the background and builds a massive indexed cache. However, if this cache becomes corrupted, the suggestd process can get stuck in a loop, consuming 100% of your CPU, draining your MacBook’s battery in hours, and failing to provide any actual suggestions.
To resolve this severe performance drain, you must forcefully purge the Core Suggestions cache using the Terminal.
Locating the Suggestions Cache
Unlike standard application preferences, the Core Suggestions database contains highly sensitive personal data extracted from your private emails and messages. Therefore, it is stored in a protected system directory within your user library.
The database files are located at: ~/Library/Suggestions/
Purging the Database via Terminal
You can clear this directory safely using the Terminal. Because the directory is located within your user profile, you do not need root (sudo) privileges, but you must ensure you target the correct path.
- Open the Terminal application.
- Execute the following command to forcefully remove all files and SQLite databases within the Suggestions directory:
rm -rf ~/Library/Suggestions/*Press Enter. The command will execute silently.
Warning: Ensure you include the tilde (~) at the beginning of the path, which represents your specific user home directory.
Restarting the suggestd Daemon
Deleting the database from the hard drive does not solve the CPU spike immediately. The background daemon (suggestd) is still running in memory, furiously trying to write to the database files you just deleted.
You must forcefully terminate the daemon so that macOS’s launchd system can restart it cleanly.
killall suggestdPress Enter. The CPU usage will instantly drop back down to normal levels.
The Rebuilding Phase
When the suggestd daemon restarts, it will realize its cache directory is empty. It will generate a fresh, uncorrupted SQLite database.
Over the next 24 to 48 hours, macOS will slowly and efficiently re-parse your recent emails, calendar events, and messages in the background to rebuild its contextual knowledge. During this time, you may notice fewer proactive suggestions, but your battery life and system performance will be permanently restored.