processes to be running simultaneously.  Also, now autovacuum processes do not
count towards the max_connections limit; they are counted separately from
regular processes, and are limited by the new GUC variable
autovacuum_max_workers.

The launcher now has intelligence to launch workers on each database every
autovacuum_naptime seconds, limited only on the max amount of worker slots
available.

Also, the global worker I/O utilization is limited by the vacuum cost-based
delay feature.  Workers are "balanced" so that the total I/O consumption does
not exceed the established limit.  This part of the patch was contributed by
ITAGAKI Takahiro.

Per discussion.

a replan.  I had originally thought this was not necessary, but the new
SPI facilities create a path whereby queries planned with non-default
options can get into the cache, so it is necessary.

Pavel Stehule, reworked a bit by Tom.

access to the planner's cursor-related planning options, and provide new
FETCH/MOVE routines that allow access to the full power of those commands.
Small refactoring of planner(), pg_plan_query(), and pg_plan_queries()
APIs to make it convenient to pass the planning options down from SPI.

This is the core-code portion of Pavel Stehule's patch for scrollable
cursor support in plpgsql; I'll review and apply the plpgsql changes
separately.

possibly be any useful pathkeys --- to wit, queries with neither any
join clauses nor any ORDER BY request.  It's nearly free to check for
this case and it saves a useful fraction of the planning time for simple
queries.

"Server-side support of all encodings" around 2007/3/26.
initdb required.

< 	o Consider reducing on-disk varlena length from four to two
< 	  because a heap row cannot be more than 64k in length
> 	o Consider reducing on-disk varlena length from four bytes to
> 	  two because a heap row cannot be more than 64k in length

ITAGAKI Takahiro

If this breaks things due to missing libxslt, then I'll have to
revert it, but let's see if it breaks the buildfarm.

Workarounds in case libxslt is missing include:
. don't configure with libxml, or
. don't build contrib modules from the contrib Makefile (use the individual module Makefiles instead), or
. change the xml2 Makefile

ITAGAKI Takahiro

EXPLAIN ANALYZE can sometimes be significantly slower than running
the same query normally, and make some minor markup improvements.

ref page (sorry, my fault!), and simplify the coding of
ResetTempTableNamespace().

> * -Add RESET SESSION command to reset all session state

fast flow of new fsync requests can prevent mdsync() from ever completing.
This was an unforeseen consequence of a patch added in Mar 2006 to prevent
the fsync request queue from overflowing.  Problem identified by Heikki
Linnakangas and independently by ITAGAKI Takahiro; fix based on ideas from
Takahiro-san, Heikki, and Tom.

Back-patch as far as 8.1 because a previous back-patch introduced the problem
into 8.1 ...

report from David Darville.  Back-patch as far as 8.1, which may or may not
have the problem but it seems a safe change anyway.

reviewed by Neil Conway. This patch adds the following DDL command
variants: RESET SESSION, RESET TEMP, RESET PLANS, CLOSE ALL, and
DEALLOCATE ALL. RESET SESSION is intended for use by connection
pool software and the like, in order to reset a client session
to something close to its initial state.

Note that while most of these command variants can be executed
inside a transaction block (but are not transaction-aware!),
RESET SESSION cannot. While this is inconsistent, it is intended
to catch programmer mistakes: RESET SESSION in an open transaction
block is probably unintended.

< 	o Allow single-byte header storage for arrays
> 	o Allow single-byte header storage for array elements

(original code *always* created a full-page image for the left page, thus
leaving the intended savings unrealized), avoid risk of not having enough room
on the page during xlog restore, squeeze out another couple bytes in the xlog
record, clean up neglected comments.

> 	o Allow single-byte header storage for arrays

> 	o Have WITH CONSTRAINTS also create constraint indexes
> 	  http://archives.postgresql.org/pgsql-patches/2007-04/msg00149.php

index types can be reliably distinguished by examining the special space
on an index page.  Per my earlier proposal, plus the realization that
there's no need for btree's vacuum cycle ID to cycle through every possible
16-bit value.  Restricting its range a little costs nearly nothing and
eliminates the possibility of collisions.
Memo to self: remember to make bitmap indexes play along with this scheme,
assuming that patch ever gets accepted.

* Simplify ability to create partitioned tables
>   http://archives.postgresql.org/pgsql-hackers/2007-04/msg00151.php

and vacuumdb.
ITAGAKI Takahiro, with minor fixes from me.

> 	o -Make CLUSTER preserve recently-dead tuples per MVCC requirements

Patch contributed by Pavan Deolasee. Along with Japanese doc
modification by Tatsuo Ishii.

> 	o -Add more logical syntax CLUSTER table USING index;

Holger Schurig

contrib/pgbuffercache.

Greg Smith

confusion.