* "Too many links" error.

This commit is contained in:
Eelco Dolstra 2006-09-12 09:29:28 +00:00
parent 01d169f817
commit f00bc4c94c

View file

@ -72,4 +72,44 @@ other.</para>
</sect1>
<sect1><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 a 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.</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 doesnt 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>
</sect1>
</appendix>