What you will achieve
Fix Spotlight when search returns nothing, indexing never finishes, or mdworker hogs CPU.
Spotlight indexes file metadata for instant search. Reindexing after macOS upgrade is normal; eternal indexing is not. mdworker CPU spikes should settle. Privacy exclusions trade search coverage for performance on huge folders you never search.
1) Confirm indexing
Spotlight menu shows “Indexing…” — wait after major copy or update. Can take hours on large drives.
2) Rebuild index
- System Settings → Siri & Spotlight → Spotlight Privacy.
- Add Macintosh HD — wait 30 seconds — remove it. Forces reindex.
Or Terminal:
sudo mdutil -E /3) Exclude heavy paths
Add Virtual Machines, node_modules, or backup disks to Privacy to stop reindexing churn — search won’t cover those folders.
4) mdworker runaway
Activity Monitor — quit stuck mdworker processes; if repeats, check external drive causing errors — disconnect failing disk.
5) Third-party search
Alfred and HoudahSpot use same index — fixing Spotlight fixes them. If only Mail search broken, rebuild mailbox in Mail.
6) mdimport plugins
Third-party apps install Spotlight importers — corrupt importer crashes mdworker on specific file types. Move suspect files out of Documents temporarily to see if indexing completes.
7) SIP and indexing
System Integrity Protection blocks indexing some system paths — normal. Do not disable SIP to “fix” Spotlight.
8) Reindex single volume
sudo mdutil -i on /Volumes/ExternalName
sudo mdutil -E /Volumes/ExternalNameFor external APFS without adding entire disk to Privacy exclusion.
Verify
Spotlight finds known file by name; CPU normal after index completes; no eternal “Indexing” banner.
9) mds_stores memory
Spotlight metadata server may use RAM after huge index — restart lowers footprint. Persistent multi-GB mds_stores after week suggests exclude video production scratch disks from index.
Additional troubleshooting notes
If steps above do not resolve the issue on the first attempt, reboot once, confirm System Settings → General → Software Update is current, and retry with a second administrator account to rule out profile or keychain corruption in your daily user. Document exact error text from Console.app with timestamp — vague “it still fails” without logs wastes support time. On Apple Silicon, re-test after full shutdown (not just restart) because firmware and Thunderbolt controllers reset only on cold boot. Intel Macs should repeat test in Safe Mode to bypass third-party login items. Before erase or keychain reset, verify Time Machine or clone backup completed — batch 3 guides assume Monterey/Ventura/Sonoma/Sequoia paths in System Settings; search Spotlight for renamed panes if your macOS version labels differ slightly.