From 6f3a13ff058f15d565a30c16c0c2cb14cc994e42 Mon Sep 17 00:00:00 2001
From: Simon Riggs <simon@2ndQuadrant.com>
Date: Mon, 6 Mar 2017 16:48:12 +0530
Subject: [PATCH] Enhance docs for ALTER TABLE lock levels of storage parms

As requested by Robert Haas
---
 doc/src/sgml/ref/alter_table.sgml | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index da431f8369..8b251f9e5d 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -568,10 +568,17 @@ ALTER TABLE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
       That can be done with <link linkend="SQL-VACUUM">VACUUM
       FULL</>, <xref linkend="SQL-CLUSTER"> or one of the forms
       of <command>ALTER TABLE</> that forces a table rewrite.
+      For planner related parameters, changes will take effect from the next
+      time the table is locked so currently executing queries will not be
+      affected.
      </para>
 
      <para>
-      Changing fillfactor and autovacuum storage parameters acquires a <literal>SHARE UPDATE EXCLUSIVE</literal> lock.
+      <literal>SHARE UPDATE EXCLUSIVE</literal> lock will be taken for 
+      fillfactor and autovacuum storage parameters, as well as the
+      following planner related parameters:
+      effective_io_concurrency, parallel_workers, seq_page_cost
+      random_page_cost, n_distinct and n_distinct_inherited.
      </para>
 
      <note>