pgsql: Backport fsync queue compaction logic to all supported branches. - Mailing list pgsql-committers

Backport fsync queue compaction logic to all supported branches.

This backports commit 7f242d880b5b5d9642675517466d31373961cf98,
except for the counter in pg_stat_bgwriter.  The underlying problem
(namely, that a full fsync request queue causes terrible checkpoint
behavior) continues to be reported in the wild, and this code seems
to be safe and robust enough to risk back-porting the fix.

Branch
------
REL8_4_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/5cea1b0a8cfa25bdd31dcc1498e815b8aa72c49d

Modified Files
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src/backend/postmaster/bgwriter.c |  129 ++++++++++++++++++++++++++++++++++---
src/backend/storage/smgr/md.c     |    8 ++-
2 files changed, 127 insertions(+), 10 deletions(-)