<listitem>
<!--
-Created from "Improve hash bucket split performance" item
+Copied here from this commit:
+Author: Robert Haas <rhaas@postgresql.org>
+2017-04-03 [ea69a0dea] Expand hash indexes more gradually.
-->
<para>
<application>pg_upgrade</>-ed hash indexes from previous major Postgres versions must be rebuilt.
</para>
<para>
-Major hash index performance improvements necessitated this requirement.
+Major hash storage improvements necessitated this requirement.
</para>
</listitem>
<listitem>
<!--
-Author: Robert Haas <rhaas@postgresql.org>
-2017-03-14 [c11453ce0] hash: Add write-ahead logging support.
+Author: Andrew Dunstan <andrew@dunslane.net>
+2017-03-31 [e306df7f9] Full Text Search support for <type>JSON</> and <type>JSONB</>
-->
<para>
-Add write-ahead logging support to hash indexes (Amit Kapila)
+Add full text search support for <type>JSON</> and <type>JSONB</> (Dmitry Dolgov)
</para>
<para>
-This makes hash indexes crash-safe and replicated, and removes the
-warning message about their use.
+This is accessed via <function>ts_headline()</> and to_tsvector. RIGHT SECTION?
</para>
</listitem>
<listitem>
<!--
-Author: Robert Haas <rhaas@postgresql.org>
-2016-11-30 [6d46f4783] Improve hash index bucket split behavior.
-Author: Robert Haas <rhaas@postgresql.org>
-2017-02-07 [293e24e50] Cache hash index's metapage in rel->rd_amcache.
-Author: Robert Haas <rhaas@postgresql.org>
-2017-02-27 [b0f18cb77] hash: Refactor bucket squeeze code.
-Author: Robert Haas <rhaas@postgresql.org>
-2017-02-27 [30df93f69] hash: Refactor overflow page allocation.
-Author: Robert Haas <rhaas@postgresql.org>
-2017-04-03 [ea69a0dea] Expand hash indexes more gradually.
+Author: Tom Lane <tgl@sss.pgh.pa.us>
+2016-08-23 [77e290682] Create an SP-GiST opclass for inet/cidr.
-->
<para>
-Improve hash bucket split performance by reducing locking requirements
-(Amit Kapila, Mithun Cy)
+Add <acronym>SP-GiST</> index support for <type>INET</> and <type>CIDR</> data types (Emre Hasegeli)
</para>
<para>
-Also cache hash index meta-information for faster lookups. Additional
-hash performance improvements have also been made.
+These data types already had GiST support.
</para>
</listitem>
<listitem>
<!--
-Author: Robert Haas <rhaas@postgresql.org>
-2017-03-15 [6977b8b7f] Port single-page btree vacuum logic to hash indexes.
+Author: Teodor Sigaev <teodor@sigaev.ru>
+2017-03-23 [218f51584] Reduce page locking in <acronym>GIN</> vacuum
-->
<para>
-Allow single-page hash pruning (Ashutosh Sharma)
+Reduce page locking during vacuuming of <acronym>GIN</> indexes (Andrey Borodin)
</para>
</listitem>
<listitem>
<!--
-Author: Andrew Dunstan <andrew@dunslane.net>
-2017-03-31 [e306df7f9] Full Text Search support for <type>JSON</> and <type>JSONB</>
+Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
+2017-04-01 [7526e1022] BRIN auto-summarization
-->
<para>
-Add full text search support for <type>JSON</> and <type>JSONB</> (Dmitry Dolgov)
+Cause <acronym>BRIN</> index summarization to happen more aggressively (Álvaro
+Herrera)
</para>
<para>
-This is accessed via <function>ts_headline()</> and to_tsvector. RIGHT SECTION?
+Specifically, summarize the previous page range when a new page range is
+created.
</para>
</listitem>
<listitem>
<!--
-Author: Tom Lane <tgl@sss.pgh.pa.us>
-2016-08-23 [77e290682] Create an SP-GiST opclass for inet/cidr.
+Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
+2017-04-01 [c655899ba] BRIN de-summarization
-->
<para>
-Add <acronym>SP-GiST</> index support for <type>INET</> and <type>CIDR</> data types (Emre Hasegeli)
+Add function <function>brin_desummarize_range()</> to remove <acronym>BRIN</> summarization of a
+specified range (Álvaro Herrera)
</para>
<para>
-These data types already had GiST support.
+This allows future <acronym>BRIN</> index summarization to be more compact. CLARIFY
</para>
</listitem>
+ </itemizedlist>
+
+ <sect5>
+ <title><link linkend="indexes-types">Hash Indexes</link></title>
+
+ <itemizedlist>
+
<listitem>
<!--
-Author: Teodor Sigaev <teodor@sigaev.ru>
-2017-03-23 [218f51584] Reduce page locking in <acronym>GIN</> vacuum
+Author: Robert Haas <rhaas@postgresql.org>
+2017-03-14 [c11453ce0] hash: Add write-ahead logging support.
-->
<para>
-Reduce page locking during vacuuming of <acronym>GIN</> indexes (Andrey Borodin)
+Add write-ahead logging support to hash indexes (Amit Kapila)
+</para>
+
+<para>
+This makes hash indexes crash-safe and replicated, and removes the
+warning message about their use.
</para>
</listitem>
<listitem>
<!--
-Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
-2017-04-01 [7526e1022] BRIN auto-summarization
+Author: Robert Haas <rhaas@postgresql.org>
+2016-11-30 [6d46f4783] Improve hash index bucket split behavior.
+Author: Robert Haas <rhaas@postgresql.org>
+2017-02-07 [293e24e50] Cache hash index's metapage in rel->rd_amcache.
+Author: Robert Haas <rhaas@postgresql.org>
-->
<para>
-Cause <acronym>BRIN</> index summarization to happen more aggressively (Álvaro
-Herrera)
+Improve hash bucket split performance by reducing locking requirements
+(Amit Kapila, Mithun Cy)
</para>
<para>
-Specifically, summarize the previous page range when a new page range is
-created.
+Also cache hash index meta-information for faster lookups.
</para>
</listitem>
<listitem>
<!--
-Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
-2017-04-01 [c655899ba] BRIN de-summarization
+Author: Robert Haas <rhaas@postgresql.org>
+2017-02-27 [b0f18cb77] hash: Refactor bucket squeeze code.
+Author: Robert Haas <rhaas@postgresql.org>
+2017-02-27 [30df93f69] hash: Refactor overflow page allocation.
+Author: Robert Haas <rhaas@postgresql.org>
+2017-04-03 [ea69a0dea] Expand hash indexes more gradually.
-->
<para>
-Add function <function>brin_desummarize_range()</> to remove <acronym>BRIN</> summarization of a
-specified range (Álvaro Herrera)
+Improve efficiency of hash index growth (Amit Kapila, Mithun Cy)
</para>
+</listitem>
+<listitem>
+<!--
+Author: Robert Haas <rhaas@postgresql.org>
+2017-03-15 [6977b8b7f] Port single-page btree vacuum logic to hash indexes.
+-->
<para>
-This allows future <acronym>BRIN</> index summarization to be more compact. CLARIFY
+Allow single-page hash pruning (Ashutosh Sharma)
</para>
</listitem>
- </itemizedlist>
-
- </sect4>
+ </itemizedlist>
- <sect4>
- <title>Locking</title>
+ </sect5>
- <itemizedlist>
+ </sect4>
+
+ <sect4>
+
+ <title>Locking</title>
+
+ <itemizedlist>
<listitem>
<!--