diff --git a/reference/apcu/ini.xml b/reference/apcu/ini.xml
index 65ede08a3233..471d6b527b64 100644
--- a/reference/apcu/ini.xml
+++ b/reference/apcu/ini.xml
@@ -77,9 +77,9 @@
      </row>
      <row>
       <entry><link linkend="ini.apcu.entries-hint">apc.entries_hint</link></entry>
-      <entry>4096</entry>
+      <entry>512 * apc.shm_size</entry>
       <entry><constant>INI_SYSTEM</constant></entry>
-      <entry></entry>
+      <entry>Prior to APcu 5.1.25, the default was 4096</entry>
      </row>
      <row>
       <entry><link linkend="ini.apcu.ttl">apc.ttl</link></entry>