mercurial/help/config.txt

--- a/mercurial/help/config.txt	Mon Nov 20 10:27:41 2017 -0800
+++ b/mercurial/help/config.txt	Sun Dec 17 11:26:25 2017 -0800
@@ -2563,6 +2563,10 @@
 directory updates in parallel on Unix-like systems, which greatly
 helps performance.
 
+``enabled``
+    Whether to enable workers code to be used.
+    (default: true)
+
 ``numcpus``
     Number of CPUs to use for parallel operations. A zero or
     negative value is treated as ``use the default``.