[Hello71]

unless you're exclusively running shell built-ins, doesn't running any command at all potentially cause a disk scan

[nyuszika7h]

Usually the shell creates a cache of commands on start, which can be refreshed with `hash -r`.

[yissp]

As far as I can tell the hash table is initially empty after you first start the shell. At least, that's the case for bash.

  $ hash
  hash: hash table empty