pgsql: Allow per-tablespace effective_io_concurrency

Allow per-tablespace effective_io_concurrency

Per discussion, nowadays it is possible to have tablespaces that have
wildly different I/O characteristics from others.  Setting different
effective_io_concurrency parameters for those has been measured to
improve performance.

Author: Julien Rouhaud
Reviewed by: Andres Freund

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/1aba62ec635f5852bc45ce65482366e541e61ff5

Modified Files
--------------
doc/src/sgml/config.sgml                  |    5 ++-
doc/src/sgml/ref/create_tablespace.sgml   |   17 ++++----
src/backend/access/common/reloptions.c    |   16 +++++++-
src/backend/executor/nodeBitmapHeapscan.c |   35 ++++++++++++----
src/backend/storage/buffer/bufmgr.c       |   63 ++++++++++++++++++++++++++++-
src/backend/utils/cache/spccache.c        |   12 ++++++
src/backend/utils/misc/guc.c              |   45 ++-------------------
src/bin/psql/tab-complete.c               |    2 +-
src/include/commands/tablespace.h         |    1 +
src/include/nodes/execnodes.h             |    4 +-
src/include/storage/bufmgr.h              |    7 ++++
src/include/utils/spccache.h              |    1 +
12 files changed, 145 insertions(+), 63 deletions(-)