savehist-save-minibuffer-history

savehist-save-minibuffer-history is a variable defined in `savehist.el'.
Its value is

t

Documentation:
If non-nil, save all recorded minibuffer histories.
If you want to save only specific histories, use `savehist-save-hook'
to modify the value of `savehist-minibuffer-history-variables'.

You can customize this variable.