diff --git a/CHANGES b/CHANGES
index ebbf5222f4..e76cf6da5d 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,8 @@
+5096.	[func]		Use multiple event loops in socket code, and
+			make network threads CPU-affinitive.  This
+			significantly improves performance on large
+			systems. [GL #666]
+
 5095.	[test]		Converted all unit tests from ATF to CMocka;
 			removed the source code for the ATF libraries.
 			Build with "configure --with-cmocka" to enable
diff --git a/doc/arm/notes.xml b/doc/arm/notes.xml
index 04e226141a..d3a0750246 100644
--- a/doc/arm/notes.xml
+++ b/doc/arm/notes.xml
@@ -131,6 +131,15 @@
 
   <section xml:id="relnotes_features"><info><title>New Features</title></info>
     <itemizedlist>
+      <listitem>
+	<para>
+	  Task manager and socket code have been substantially modified.
+	  The manager uses per-cpu queues for tasks and network stack runs
+	  multiple event loops in CPU-affinitive threads. This greatly
+	  improves performance on large systems, especially when using
+	  multi-queue NICs.
+	</para>
+      </listitem>
       <listitem>
 	<para>
 	  A new secondary zone option, <command>mirror</command>,