macOS Spotlight

Spotlight’s search index (mds/mdworker) occasionally corrupts — searches return stale or missing results, or mds pins the CPU. Rebuilding the index fixes it.

Force a Full Reindex

sudo mdutil -a -i off      # disable indexing on all volumes
sudo rm -rf /.Spotlight-V100   # delete the existing index
sudo mdutil -a -i on       # re-enable indexing
sudo mdutil -E             # erase and rebuild from scratch

Reindexing runs in the background and can take a while; CPU/fan spike until it finishes.

Useful Companions

mdutil -s /                 # index status for a volume
mdfind "query"              # Spotlight search from the CLI
mdls file                   # show a file's Spotlight metadata

Exclude a folder

Add paths under System Settings → Spotlight → Search Privacy to keep large build dirs (node_modules, caches) out of the index.