[pgpool-committers: 4105] pgpool: Importing the latest changes in the MemoryManager API from Post

[Muhammad Usama]

Importing the latest changes in the MemoryManager API from PostgreSQL code.

Pgpool-II has borrowed the MemoryManager from PostgreSQL source and recently
there have been some performance updates made to the PostgreSQL's
memory manager, from which Pgpool-II can also benefit from.
This need was identified by the reporter of issue: "315: High CPU usage when
commiting large transactions and using in (shared) memory cache"

Branch
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V3_5_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=e83a2745c8be848fb35ea9d7184c8d025bfbb60d

Modified Files
--------------
src/include/parser/pg_config_manual.h |   9 +
src/include/pool_type.h               |  16 +
src/include/utils/memnodes.h          |  36 +-
src/include/utils/memutils.h          | 105 ++++--
src/include/utils/palloc.h            |  91 +++--
src/utils/mmgr/aset.c                 | 482 ++++++++++++--------------
src/utils/mmgr/mcxt.c                 | 612 ++++++++++++++++++++++++----------
7 files changed, 823 insertions(+), 528 deletions(-)