The out/readfuncs.c support for AlterTableStmt.comptypeArrayOid was
missing. Because of that, the segments didn't get the OID of the composite
type's array type from master, and allocated it on their own.

tuple.
This closes #649

Squashed commit of the following:

commit 96f415bc1744533e96a74bcc85016ff5df65d06e
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Thu Apr 21 15:08:49 2016 -0700

    Don't call prepare for execution if no generator is registered

commit 5318e9214a3bbc237c0d79017cdef02538c4e711
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Thu Apr 21 11:35:22 2016 -0700

    Adding if codegen protection in starting active manager and while
    deleting manager

commit 12b0045d51a5b056b32a6cc9ef370e6d9af315fd
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Fri Apr 15 14:33:55 2016 -0700

    Updating Readme for Codegen GPDB Function

commit d17119c5d8ce9a706b3321d5e7ad41f419fddbdc
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 13:25:14 2016 -0700

    Add documentation for how to codegen in README.md

commit d711be4bb044592e7f97bf31ceb5f32337ad6d03
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 11:19:03 2016 -0700

    Fixing doxygen namespace addtogroup

commit e34131bcc9bb3d36c5e8995e1a0efe11fbd55417
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 11:17:32 2016 -0700

    Changing CodeGen to Codegen

commit bedfcca80b5f1ff796783ca7c2035d920ae86c4e
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 10:51:39 2016 -0700

    Fix cpplint error

commit 32f89feedba655e1242529c78a54faf01ddf32bf
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 10:48:49 2016 -0700

    Change regular version of generated to regular version of target in comment

commit d1da2824c08e34eb7139b08cd9d2aff19bf008e7
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Wed Apr 13 10:42:09 2016 -0700

    Made GetFunctionPointer and CreateFunction to take typedef of function type as only public api

commit 9f48f77bd9fc50c7d29a4e8f7700452ef88dc79f
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 17:18:24 2016 -0700

    Rename doCodegeneration to GenerateCodeInternal

commit 9884d07f4c6ab08d9ccca8d07b80974081cda1fa
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 17:15:55 2016 -0700

    fix cpplint error

commit c21b3bee3e289675fc13017688269b40e26efa11
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 17:08:16 2016 -0700

    Update comments

commit f016bb582af65e84def1b55917017008e292d45b
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 17:01:19 2016 -0700

    Adding assert in static setToRegular function

commit 93a791a4ec415313933dd5b7c1ae17dbdd6193a6
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 16:49:15 2016 -0700

    Removing decltype in Slotdeformtype codegen since we know the functype

commit ed95193d0991cb24fd68f6d9a473de630f297b0c
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 16:45:49 2016 -0700

    Fixed compiler / unit test failure
    Changed InitCodeGen to InitCodegen

commit 3c95c9efdd4336e100a86748b0e87d79f07bcc11
Author: Karthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Date:   Tue Apr 12 16:28:24 2016 -0700

    Changing CodeGen back to Codegen while cherry-picking

commit 4e24ef22bcf54edc00c2a0d1f9f9703364cdf5ba
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Tue Apr 12 11:08:42 2016 -0700

    Changing auto to actual type

commit 1d92fc190dda3ec866edc83d56d9eca9fe90a63a
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Tue Apr 12 10:44:49 2016 -0700

    fix indent in codegen_utils

commit ea6fa787a2332f94b8d20d24825ba1f0a240d02e
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 17:25:53 2016 -0700

    Adding codegen guc to wrapper function so related function not executed when codegen guc is disabled

commit f1cd7d80d8d81f3565f3ab12cb94a3c4cc58c44a
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 17:13:24 2016 -0700

    Changing bool to unsigned int in codegen_wrapper.h

commit 7ef462540a312d077b332c732c125c55dedb6b14
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 16:59:08 2016 -0700

    Fix based on lint complain

commit ddc55cec0d579a03cb9e2303efa6d74f5183979f
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 16:19:48 2016 -0700

    Removing commented code from unittest

commit 28b8886ed2bfdc854aa38f871a41536c1e6cef29
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 16:17:45 2016 -0700

    Chaging auto in for to actual type

commit ad8d78e07e9b789f4d8ae3c6ccc3cea1a05089c0
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 16:13:21 2016 -0700

    * Handle return value of SetToGenerated from PrepareForExecution
    * Change size_t to unsigned integer

commit d46ee8be414b3ac2a9ea7ef899f29cef3df145c7
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 15:30:40 2016 -0700

    Introducing template function to do enroll for any type of generator

commit 83428605f906e28d0fc994dcc311e0cc3e6d9e12
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 14:41:11 2016 -0700

    Changing manager to take module name as argument

commit b88aa40f89860e7c15503365ea304d2392f71cda
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 14:27:31 2016 -0700

    adding more comments to SlotDeformTupleCodeGenInfo and unique counter

commit df1b704548fcbc1b43524064eb2f024995eea865
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 14:08:34 2016 -0700

    Change test target to have ext .t and adding gitignore for that extension

commit 9ee3521ca687c4ea7f13d15893f47146ecdb5277
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 13:59:57 2016 -0700

    Add target_include_directories for test library header file

commit effb7dc165b4c7094731dc39e0872741b28b2e6a
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Mon Apr 11 13:36:50 2016 -0700

    Move all possible ifdef from gpdb to codegen_wrapper based on pull request comments

commit 989b96a91c1e843577b5f24623d1e4a6b810394c
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Fri Apr 8 10:43:17 2016 -0700

    fixing comments for GetOrigFuncName in codegen_interface

commit 665de065c34ea13abcec8c5f3a3336558dae501f
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Fri Apr 8 10:27:31 2016 -0700

    Disabling codegen guc by default

commit ec34513e86dea95bd36ee528724273c1c19e7062
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Thu Apr 7 16:28:43 2016 -0700

    Fixed comments space/tab so it aligned in different editor

commit 35a60fe2fd053a5babd1820302afad95c5c2635f
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Thu Apr 7 16:12:08 2016 -0700

    Fixing coding style based on cpplint

commit 9477dcf6c0a7ffcca77b9f2c62c7340d13f474aa
Author: Karthikeyan Jambu Rajaraman <krajaraman@pivotal.io>
Date:   Thu Apr 7 13:37:01 2016 -0700

    Adding USE_CODEGEN ifdef

commit 142ffc1416341a3ac1d0fe37a83577168f2ec166
Author: Shreedhar Hardikar <shardikar@pivotal.io>
Date:   Tue Apr 5 22:21:19 2016 +0000

    Make codegen work with GPDB unit test framework

commit 9dca9507dd933a5517bee3ca34615c09c23c1728
Author: Shreedhar Hardikar <shardikar@pivotal.io>
Date:   Mon Apr 4 22:10:21 2016 +0000

    Add gpcodegen_mock.c

commit 41d515ff0342d3df3b0853ad91731f6d1d75843c
Author: Shreedhar Hardikar <shardikar@pivotal.io>
Date:   Mon Apr 4 21:46:34 2016 +0000

    Remove unneccessary header file includes in codegen

commit 14c5e14b9834197693b1ef56efa96386cfe049c5
Author: Foyzur Rahman <frahman@gmail.com>
Date:   Tue Apr 12 14:49:51 2016 -0700

    Integrate codegen framework and make simple external call to slot deform tuple
Signed-off-by: NKarthikeyan Jambu Rajaraman <karthi.jrk@gmail.com>
Signed-off-by: NFoyzur Rahman <frahman@gmail.com>

Removed one test that was checking for a memory leak by attempting to run the system out of memory.
Refactored one test that was checking for a large insert into a table with a bitmap index.

Closes #660.

[#116336737, #117671863]

Commit 9d19664c ported a test from cdbfast to master, which uses gp_fault_inject mechanism to throw a SIGSEGV.
We remove this test because i) gp_fault_inject works only if USE_TEST_UTILS = 1, while when we test GPDB, we set USE_TEST_UTILS to 0, and ii) throwing segmentation faults in ICG is a wrong approach.

Fixes compiler warning for implicit declaration due to missing
headerfile include:

  copy.c:4143:6: warning: implicit declaration of function
     'reconstructTupleValues' is invalid in C99
     [-Wimplicit-function-declaration]

Backport from upstream and related commits are

    commit e5fe2e84
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Date:   Fri Nov 9 23:58:32 2007 +0000

        Recognize RETURN QUERY via a textual test, so that QUERY doesn't need to be
        a plpgsql keyword.  This avoids springing a new reserved word on plpgsql
        programmers.
        For consistency, handle RETURN NEXT the same way.

    commit b2b9b4d5
    Author: Neil Conway <neilc@samurai.com>
    Date:   Wed Jul 25 04:19:09 2007 +0000

        Implement RETURN QUERY for PL/PgSQL. This provides some convenient syntax
        sugar for PL/PgSQL set-returning functions that want to return the result
        of evaluating a query; it should also be more efficient than repeated
        RETURN NEXT statements. Based on an earlier patch from Pavel Stehule.

Committers: Kuien Liu and Haozhou Wang

The tests were added in commit 7d0325e4
and were not properly translated from Pivotal's internal tests to the
pg_regress tests. They now properly test CREATE RULE on AO/CO tables.

Thanks to Heikki Linnakangas for catching this issue.

`set optimizer_join_arity_for_associativity_commutativity=7` will hint
at the optimizer to stop exploring join associativity and join
commutativity transformations when an n-ary join operator has more than
7 children during optimization, pruning quite a bit of the search space.

We really shouldn't get a sentinel node here but if we for some reason
do we need/should handle it by erroring out rather than propagating the
sentinel.

Reviewed by vraghavan@

The cursor test for external table is non deterministic. The query errors out
either during DECLARE cursor or during FETCH. If the query errors out during
DECLARE and we perform a FETCH after the DECLARE an extra line of error is
produced in the output stating that the transaction has been aborted. In the
case where FETCH errors out this error is not produced in the output. This
commit adds a separate expected answer file to handle the two cases.

CodegenUtils.
This closes #648
Signed-off-by: NFoyzur Rahman <frahman@gmail.com>

Currently, the error reporting for duplicate key value violation for unique
indexes does not contain useful information for users when debugging. This
commit backports two commits from PostgreSQL (shown below) and updates our
multikey tuplesort to use the same. Now the error will display the first
instance of a duplicate key violation.

Authors: Jimmy Yih and Abhijit Subramanya

commit b680ae4b
Author: Tom Lane <tgl@sss.pgh.pa.us>
Date:   Sat Aug 1 19:59:41 2009 +0000

    Improve unique-constraint-violation error messages to include the exact
    values being complained of.

    In passing, also remove the arbitrary length limitation in the similar
    error detail message for foreign key violations.

    Itagaki Takahiro

 Conflicts:
	contrib/citext/expected/citext.out
	contrib/citext/expected/citext_1.out
	src/backend/access/common/indextuple.c
	src/backend/access/index/genam.c
	src/backend/access/nbtree/nbtinsert.c
	src/backend/utils/adt/ri_triggers.c
	src/backend/utils/adt/ruleutils.c
	src/include/access/genam.h
	src/include/access/itup.h
	src/include/utils/builtins.h
	src/test/regress/expected/alter_table.out
	src/test/regress/expected/arrays.out
	src/test/regress/expected/create_index.out
	src/test/regress/expected/plpgsql.out
	src/test/regress/expected/transactions.out
	src/test/regress/expected/uuid.out
	src/test/regress/output/constraints.source
	src/test/regress/output/tablespace.source

commit 527f0ae3
Author: Tom Lane <tgl@sss.pgh.pa.us>
Date:   Sat Aug 1 20:59:17 2009 +0000

    Department of second thoughts: let's show the exact key during unique index
    build failures, too.  Refactor a bit more since that error message isn't
    spelled the same.

 Conflicts:
	src/backend/access/nbtree/nbtinsert.c
	src/backend/utils/sort/tuplesort.c
	src/test/regress/expected/alter_table.out
	src/test/regress/expected/create_index.out

The maximal number of distributed by columns is 1600, gpdb should error out when
it exceeds the limitation. Another thing is gpdb should allocate enough memory to
hold those columns, otherwise it will cause memory overflow.

Three functions are available now:
- convert_from(bytea, name) returns text
- convert_to(text, name) returns bytea
- length(bytea, name) returns int

Related commits (partial codes are backported before OSS but not actived)

    commit a9742f12
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Date:   Wed Jan 9 23:43:54 2008 +0000

        Remove incorrect (and ill-advised anyway) pfree's in pg_convert_from and
        pg_convert_to.  Per bug #3866 from Andrew Gilligan.

    commit 02138357
    Author: Andrew Dunstan <andrew@dunslane.net>
    Date:   Mon Sep 24 01:29:30 2007 +0000

        Remove "convert 'blah' using conversion_name" facility, because if it
        produces text it is an encoding hole and if not it's incompatible
        with the spec, whatever the spec means (which we're not sure about anyway).

    commit 55613bf9
    Author: Andrew Dunstan <andrew@dunslane.net>
    Date:   Tue Sep 18 17:41:17 2007 +0000

        Close previously open holes for invalidly encoded data to enter the
        database via builtin functions, as recently discussed on -hackers.

        chr() now returns a character in the database encoding. For UTF8 encoded databases
        the argument is treated as a Unicode code point. For other multi-byte encodings
        the argument must designate a strict ascii character, or an error is raised,
        as is also the case if the argument is 0.

        ascii() is adjusted so that it remains the inverse of chr().

        The two argument form of convert() is gone, and the three argument form now
        takes a bytea first argument and returns a bytea. To cover this loss three new
        functions are introduced:
        . convert_from(bytea, name) returns text - converts the first argument from the
          named encoding to the database encoding
        . convert_to(text, name) returns bytea - converts the first argument from the
          database encoding to the named encoding
        . length(bytea, name) returns int - gives the length of the first argument in
          characters in the named encoding

    commit 75c6519f
    Author: Tatsuo Ishii <ishii@postgresql.org>
    Date:   Sun Mar 25 11:56:04 2007 +0000

        Add new encoding EUC_JIS_2004 and SHIFT_JIS_2004,
        along with new conversions among EUC_JIS_2004, SHIFT_JIS_2004 and UTF-8.
        catalog version has been bump up.

Committers: Kuien Liu and Haozhou Wang

Signed-off-by: NNikos Armenatzoglou <nikos.armenatzoglou@gmail.com>

A new version of libXML changes the output format, this patch
adapts the new "expected" file introduced in
PostgreSQL commit 085423e3.
Slight modifications by me.

This patch will not fail the current Pulse run in any way, because
the Pulse systems do not yet use the new libXML library, and therefore
are happy with xml.out and xml_1.out. I stripped down the regression
tests and this is the output without the patch:

parallel group (14 tests):  limit prepare conversion xml rowtypes copy2 polymorphism sequence without_oid temp truncate domain rangefuncs alter_table
     limit                ... ok (0,24 sec)  (diff:0,07 sec)
     copy2                ... ok (2,44 sec)  (diff:0,07 sec)
     temp                 ... ok (3,83 sec)  (diff:0,07 sec)
     domain               ... ok (7,12 sec)  (diff:0,10 sec)
     rangefuncs           ... ok (12,15 sec)  (diff:0,09 sec)
     prepare              ... ok (0,49 sec)  (diff:0,06 sec)
     without_oid          ... ok (3,49 sec)  (diff:0,07 sec)
     conversion           ... ok (1,19 sec)  (diff:0,17 sec)
     truncate             ... ok (4,03 sec)  (diff:0,06 sec)
     alter_table          ... ok (27,88 sec)  (diff:0,32 sec)
     sequence             ... ok (3,18 sec)  (diff:0,08 sec)
     polymorphism         ... ok (3,13 sec)  (diff:0,11 sec)
     rowtypes             ... ok (2,17 sec)  (diff:0,09 sec)
     xml                  ... FAILED (1,69 sec)  (diff:0,39 sec)
test variadic_parameters  ... ok (1,57 sec)  (diff:0,07 sec)
test default_parameters   ... ok (0,68 sec)  (diff:0,07 sec)

=======================
 1 of 97 tests failed.
=======================

This is the output with the patch:

parallel group (14 tests):  limit prepare conversion xml rowtypes copy2 polymorphism sequence without_oid temp truncate domain rangefuncs alter_table
     limit                ... ok (0,21 sec)  (diff:0,10 sec)
     copy2                ... ok (1,95 sec)  (diff:0,06 sec)
     temp                 ... ok (3,41 sec)  (diff:0,26 sec)
     domain               ... ok (6,67 sec)  (diff:0,19 sec)
     rangefuncs           ... ok (11,55 sec)  (diff:0,09 sec)
     prepare              ... ok (0,41 sec)  (diff:0,06 sec)
     without_oid          ... ok (2,91 sec)  (diff:0,06 sec)
     conversion           ... ok (0,96 sec)  (diff:0,15 sec)
     truncate             ... ok (3,62 sec)  (diff:0,09 sec)
     alter_table          ... ok (25,79 sec)  (diff:0,22 sec)
     sequence             ... ok (2,89 sec)  (diff:0,06 sec)
     polymorphism         ... ok (2,50 sec)  (diff:0,09 sec)
     rowtypes             ... ok (1,87 sec)  (diff:0,12 sec)
     xml                  ... ok (1,54 sec)  (diff:0,30 sec)
test variadic_parameters  ... ok (1,43 sec)  (diff:0,07 sec)
test default_parameters   ... ok (0,43 sec)  (diff:0,07 sec)

======================
 All 97 tests passed.
======================

Fix #550

It didn't do anything useful AFAICS.

* Support the aggregation transition datatype to be "internal"

Backport below commits from upstream:

    commit 22d9ddbb
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Date:   Sat Aug 14 15:47:13 2010 +0000

        Fix planner to make a reasonable assumption about the amount of memory space
        used by array_agg(), string_agg(), and similar aggregate functions that use
        "internal" as their transition datatype.  The previous coding thought this
        took *no* extra space, since "internal" is pass-by-value; but actually these
        aggregates typically consume a great deal of space.  Per bug #5608 from
        Itagaki Takahiro, and fix suggestion from Hitoshi Harada.

        Back-patch to 8.4, where array_agg was introduced.

    commit 9e0247ab
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Date:   Fri Nov 14 19:47:50 2008 +0000

        In CREATE AGGREGATE, allow the transition datatype to be "internal", but only
        if the user is superuser.  This makes available to extension modules the same
        sort of trick being practiced by array_agg().  The reason for the superuser
        restriction is that you could crash the system by connecting up an
        incompatible pair of internal-using functions as an aggregate.  It shouldn't
        interfere with any legitimate use, since you'd have to be superuser to create
        the internal-using transition and final functions anyway.

Besides, we cannot find regression tests in above commits, so we
add a set of tests for this feature, a part of them come from
legacy extension "intagg" regression tests.

Conflicts:
	src/test/regress/expected/arrays.out
	src/test/regress/sql/arrays.sql

* add tests to #588: run with role of (non-)superuser

    #588: Support the aggregate's transype to be "internal"

Normally, the aggregate's transtype can't be a pseudo-type.
However, we can allow "internal" for functions that want to
pass pointers to private data structures; but allow that only
to superusers. Here we add tests to verify this constraint.

This code was commented out without providing any useful information
so remove to reduce clutter.

This closes #606

This mirrors the check in vacuum.c, for VACUUMing external tables. This was
missed in commit f995c59f, which replaced most of the old ANALYZE with
the upstream code.

Fixes issue #395, reported by George Caragea.

Space for bit addition to nullbitmap was missed while estimating if
block has space for new delta item or not. Since adding a delta value,
adds a false bit to nullbitmap, it needs to be added in space
calculation before inserting new item to block. Missing same maybe endup
in failure during block write due to block size overflow.

The qp_query_execution test was added to the tree in commit 9d19664c
and then further updated in 29a0fec8 but it's not present in any test
schedule. Add to the greenplum_schedule to include it when running
installcheck-good.

Backport below commit from upstream:

    commit d5768dce
    Author: Tom Lane <tgl@sss.pgh.pa.us>
    Date:   Mon Feb 8 20:39:52 2010 +0000

        Create an official API function for C functions to use to check if they are
        being called as aggregates, and to get the aggregate transition state memory
        context if needed.  Use it instead of poking directly into AggState and
        WindowAggState in places that shouldn't know so much.

        We should have done this in 8.4, probably, but better late than never.

        Revised version of a patch by Hitoshi Harada.

modified:   src/backend/executor/nodeAgg.c
modified:   src/include/fmgr.h

Since we discover the apr-1-config binary during the configure stage
we might as well simplify the gpfdist Makefile by using it during
building. Also renames the APR_CONFIG variable to avoid colliding
with $APR_CONFIG using the gpAux makefile.

transaction block.

ReindexRelationList is a GPDB specific function that wraps each
reindex table operation within a separate transaction.  If the table
being reindexed is a partitioned table, each partition is reindexed in
a separate transaction.  Now that we have removed the assertion,
refactor this function to commit and start top level transcation,
rather than leaving this burden on callers.

Fixes #567.

This commit makes zlib to use palloc/pfree, by rewriting compress_zlib.c to utilize the API in gfile.c, and dispatcher to use palloc and pfree through a set of zlib wrapper functions. This enables our protection mechanisms (gp_vmem_protect_limit, runaway_detector_activation_percent) to keep the system stable by cleanly canceling a query which would otherwise cause us to run out of memory.
Signed-off-by: NNikos Armenatzoglou <nikos.armenatzoglou@gmail.com>

Fixing memory leak because of reallocation of level state per partition for every new partition. Instead, we now reallocate level state for every level in the makeWindowState.

The following repro will consume gigabytes of memory and should run out of memory, given appropriate VMEM configuration:

drop table if exists wtest;
create table wtest
(
    id integer,
    dt date,
    name character varying(100),
    created_dt date
);

insert into wtest select a, current_date + a, 'xyz' || a, current_date + (a % 10) from (select a from generate_series(1, 10000000) as a) as temp;

select row_number() over (w) as row_num,
id,
dt,
name
from wtest
window w as (partition by dt,
name,
id
order by created_dt desc
);

After the fix the same repro should consume very little memory.

In some cases, the filerep processes get stuck waiting for the spin locks on an
in memory log and the postmaster PANICs if they can't acquire a lock after
timeout period. In order to avoid locking related issues we want to avoid
acquiring the locks in the first place. This patch introduces a new guc which
will cause filerep logs to be logged to server logs and will avoid logging to
the in memory log.