Spotlight problems
Search performance does not degrade smoothly. It falls off a cliff at a size most people reach eventually.
Spotlight's index scales with content, not just file count. A million small text files cost more to index than a hundred large videos, because every word goes into an inverted index.
Two effects follow: indexing takes longer, and each query has more candidates to rank.
A single web project can hold 40,000 files in node_modules. Ten projects is 400,000 files — more than the rest of a typical Mac combined. macOS excludes node_modules by default for exactly this reason.
mds_stores regularly near the top of Activity MonitorExclude what you never search. System Settings → Siri & Spotlight → Spotlight Privacy. Adding build directories, VM images and archive volumes reduces index size dramatically.
Turn off categories you do not use. Fewer sources, less ranking.
Rebuild once, if the index is damaged rather than merely large.
Filenames average around 27 bytes. Six million files is roughly 164 MB of names — a fixed, predictable cost that does not grow with the size of the files themselves.
Scanning that is bounded by memory bandwidth rather than disk, and stays in single-digit milliseconds whether the files are text notes or 4K video. That is the structural reason a names-only index stays fast where a content index cannot.
Indirectly. What matters is the number of files and the amount of indexable text, not free space — though a nearly full disk also slows the whole system.
macOS already does by default. If you have build output elsewhere, excluding it helps.
Everywhere keeps track of every file on your Mac — including the folders Spotlight hides and drives you have unplugged. Free for a day, then $19 once.
Download for Mac