43 lines
1.5 KiB
XML
43 lines
1.5 KiB
XML
|
<chapter xmlns="http://docbook.org/ns/docbook"
|
|||
|
|
xmlns:xlink="http://www.w3.org/1999/xlink"
|
|||
|
|
xmlns:xi="http://www.w3.org/2001/XInclude"
|
|||
|
|
version="5.0"
|
|||
|
|
xml:id="ch-links-nix-store">
|
|||
|
|
|
|||
|
|
<title><quote>Too many links</quote> Error in the Nix store</title>
|
|||
|
|
|
|||
|
|
|
|||
|
|
<para>Symptom: when building something, you get an error message such as
|
|||
|
|
|
|||
|
|
<screen>
|
|||
|
|
...
|
|||
|
|
<literal>mkdir: cannot create directory `/nix/store/<replaceable>name</replaceable>': Too many links</literal></screen>
|
|||
|
|
|
|||
|
|
</para>
|
|||
|
|
|
|||
|
|
<para>This is usually because you have more than 32,000 subdirectories
|
|||
|
|
in <filename>/nix/store</filename>, as can be seen using <command>ls
|
|||
|
|
-l</command>:
|
|||
|
|
|
|||
|
|
<screen>
|
|||
|
|
$ ls -l /nix/store
|
|||
|
|
drwxrwxrwt 32000 nix nix 4620288 Sep 8 15:08 store</screen>
|
|||
|
|
|
|||
|
|
The <literal>ext2</literal> file system is limited to an inode link
|
|||
|
|
count of 32,000 (each subdirectory increasing the count by one).
|
|||
|
|
Furthermore, the <literal>st_nlink</literal> field of the
|
|||
|
|
<function>stat</function> system call is a 16-bit value.</para>
|
|||
|
|
|
|||
|
|
<para>This only happens on very large Nix installations (such as build
|
|||
|
|
machines).</para>
|
|||
|
|
|
|||
|
|
<para>Quick solution: run the garbage collector. You may want to use
|
|||
|
|
the <option>--max-links</option> option.</para>
|
|||
|
|
|
|||
|
|
<para>Real solution: put the Nix store on a file system that supports
|
|||
|
|
more than 32,000 subdirectories per directory, such as ReiserFS.
|
|||
|
|
(This doesn’t solve the <literal>st_nlink</literal> limit, but
|
|||
|
|
ReiserFS lies to the kernel by reporting a link count of 1 if it
|
|||
|
|
exceeds the limit.)</para>
|
|||
|
|
|
|||
|
|
</chapter>
|