pgsql: Add deadlock counter to pg_stat_database

Add deadlock counter to pg_stat_database

Adds a counter that tracks number of deadlocks that occurred in
each database to pg_stat_database.

Magnus Hagander, reviewed by Jaime Casanova

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/61cb8c5abb9235c3106af6c6a6e60d94cb1eee80

Modified Files
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doc/src/sgml/monitoring.sgml | 12 ++++++++-
src/backend/catalog/system_views.sql | 1 +
src/backend/postmaster/pgstat.c | 43 ++++++++++++++++++++++++++++++++-
src/backend/storage/lmgr/deadlock.c | 2 +
src/backend/utils/adt/pgstatfuncs.c | 16 ++++++++++++
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 2 +
src/include/pgstat.h | 19 +++++++++++++-
src/test/regress/expected/rules.out | 2 +-
9 files changed, 91 insertions(+), 8 deletions(-)