<refentry xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xi="http://www.w3.org/2001/XInclude" xml:id="sec-nix-collect-garbage"> <refmeta> <refentrytitle>nix-collect-garbage</refentrytitle> <manvolnum>1</manvolnum> <refmiscinfo class="source">Nix</refmiscinfo> <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> </refmeta> <refnamediv> <refname>nix-collect-garbage</refname> <refpurpose>delete unreachable store paths</refpurpose> </refnamediv> <refsynopsisdiv> <cmdsynopsis> <command>nix-collect-garbage</command> <arg><option>--delete-old</option></arg> <arg><option>-d</option></arg> <group choice='opt'> <arg choice='plain'><option>--print-roots</option></arg> <arg choice='plain'><option>--print-live</option></arg> <arg choice='plain'><option>--print-dead</option></arg> <arg choice='plain'><option>--delete</option></arg> </group> </cmdsynopsis> </refsynopsisdiv> <refsection><title>Description</title> <para>The command <command>nix-collect-garbage</command> is mostly an alias of <link linkend="rsec-nix-store-gc"><command>nix-store --gc</command></link>, that is, it deletes all unreachable paths in the Nix store to clean up your system. However, it provides an additional option <option>-d</option> (<option>--delete-old</option>) that deletes all old generations of all profiles in <filename>/nix/var/nix/profiles</filename> by invoking <literal>nix-env --delete-generations old</literal> on all profiles. Of course, this makes rollbacks to previous configurations impossible.</para> </refsection> <refsection><title>Example</title> <para>To delete from the Nix store everything that is not used by the current generations of each profile, do <screen> $ nix-collect-garbage -d</screen> </para> </refsection> </refentry>