Update runtime shared memory computations.

doc/src/sgml/runtime.sgml

 <!--
-$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.64 2001/05/07 15:55:27 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/runtime.sgml,v 1.65 2001/05/08 21:09:47 momjian Exp $
 -->
 
 <Chapter Id="runtime">
@@ -1481,7 +1481,7 @@ env PGOPTIONS='-c geqo=off' psql
       <row>
        <entry><varname>SHMMAX</></>
        <entry>Maximum size of shared memory segment (bytes)</>
-       <entry>250 kB + 8192 * buffers or infinity</entry>
+       <entry>250 kB + 8.2kB * buffers + 14.2kB * max_connections or infinity</entry>
       </row>
 
       <row>