Add mention of kern.ipc.shm_use_phys for locking shared memory.

doc/src/sgml/runtime.sgml

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-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.158 2002/11/21 06:36:08 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.159 2002/11/21 18:19:51 momjian Exp $
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 <Chapter Id="runtime">
@@ -2607,9 +2607,9 @@ options         SEMMAP=256
         <literal>option</literal> singular.)
        </para>
        <para>
-        You may also want to use the <application>sysctl</> setting to
+        You might also want to use the <application>sysctl</> setting to
         lock shared memory into RAM and prevent it from being paged out
-        to swap.
+        to swap, e.g. <literal>kern.ipc.shm_use_phys</>.
        </para>
       </listitem>
      </varlistentry>