about summary refs log tree commit diff
path: root/doc/manual/troubleshooting/links-nix-store.xml
diff options
context:
space:
mode:
Diffstat (limited to 'doc/manual/troubleshooting/links-nix-store.xml')
-rw-r--r--doc/manual/troubleshooting/links-nix-store.xml43
1 files changed, 43 insertions, 0 deletions
diff --git a/doc/manual/troubleshooting/links-nix-store.xml b/doc/manual/troubleshooting/links-nix-store.xml
new file mode 100644
index 000000000000..5efec8e8bc53
--- /dev/null
+++ b/doc/manual/troubleshooting/links-nix-store.xml
@@ -0,0 +1,43 @@
+<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>
\ No newline at end of file