<refentry> <refnamediv> <refname>nix-collect-garbage</refname> <refpurpose>remove unreachable store paths</refpurpose> </refnamediv> <refsynopsisdiv> <cmdsynopsis> <command>nix-collect-garbage</command> <group choice='opt'> <arg choice='plain'><option>--print-live</option></arg> <arg choice='plain'><option>--print-dead</option></arg> </group> <arg><option>--min-age</option> <replaceable>age</replaceable></arg> </cmdsynopsis> </refsynopsisdiv> <refsection> <title>Description</title> <para> The command <command>nix-collect-garbage</command> performs a garbage collection on the Nix store: any paths in the Nix store that are garbage (not reachable from a set of root store expressions) are deleted. </para> <para> The roots of the garbage collector are the store expressions mentioned in the files in the directory <filename><replaceable>prefix</replaceable>/var/nix/gcroots</filename>. By default, the roots are all user environments in <filename><replaceable>prefix</replaceable>/var/nix/profiles</filename>. You can register other store expressions as roots by writing the full path of the store expression to an arbitrary file in the <filename>gcroots</filename> directory (or a subdirectory thereof). </para> </refsection> <refsection> <title>Options</title> <variablelist> <varlistentry> <term><option>--print-live</option> / <option>--print-dead</option></term> <listitem> <para> These options cause the set of live or dead paths to be printed, respectively, rather than performing an actual garbage collector. They correspond exactly with the sub-operations in <command>nix-store <option>--gc</option></command>. </para> </listitem> </varlistentry> <varlistentry> <term><option>--min-age</option> <replaceable>age</replaceable></term> <listitem> <para> This option corresponds to the <option>--min-age</option> option in <command>nix-store <option>--gc</option></command>. </para> </listitem> </varlistentry> </variablelist> </refsection> <refsection> <title>Examples</title> <para> To delete all unreachable paths, just do: <screen> $ nix-collect-garbage</screen> </para> </refsection> </refentry>