Use group updates when setting transaction status in clog.
Commit 0e141c0fbb211bdd23783afa731e3eef95c9ad7a introduced a mechanism
to reduce contention on ProcArrayLock by having a single process clear
XIDs in the procArray on behalf of multiple processes, reducing the
need to hand the lock around. A previous attempt to introduce a similar
mechanism for CLogControlLock in ccce90b398673d55b0387b3de66639b1b30d451b
crashed and burned, but the design problem which resulted in those
failures is believed to have been corrected in this version.
Amit Kapila, with some cosmetic changes by me. See the previous commit
message for additional credits.
Discussion: http://postgr.es/m/CAA4eK1KudxzgWhuywY_X=yeSAhJMT4DwCjroV5Ay60xaeB2Eew@mail.gmail.com
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/baaf272ac908ea27c09076e34f62c45fa7d1e448
Modified Files
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doc/src/sgml/monitoring.sgml | 6 +-
src/backend/access/transam/clog.c | 264 ++++++++++++++++++++++++++++++++++++--
src/backend/postmaster/pgstat.c | 3 +
src/backend/storage/lmgr/proc.c | 9 ++
src/include/pgstat.h | 1 +
src/include/storage/proc.h | 14 ++
6 files changed, 285 insertions(+), 12 deletions(-)