@@ 730,6 730,9 @@ If the current generation matches, it is deleted atomically---i.e., by
switching to the previous available generation. Note that the zeroth
generation is never deleted.
+Note that deleting generations prevents roll-back to them.
+Consequently, this command must be used with care.
+
@end table
@node Packages with Multiple Outputs
@@ 797,6 800,12 @@ deleted. The set of garbage collector roots includes default user
profiles, and may be augmented with @command{guix build --root}, for
example (@pxref{Invoking guix build}).
+Prior to running @code{guix gc --collect-garbage} to make space, it is
+often useful to remove old generations from user profiles; that way, old
+package builds referenced by those generations can be reclaimed. This
+is achieved by running @code{guix package --delete-generations}
+(@pxref{Invoking guix package}).
+
The @command{guix gc} command has three modes of operation: it can be
used to garbage-collect any dead files (the default), to delete specific
files (the @code{--delete} option), or to print garbage-collector