Track shared buffer hits in pg_stat_io Among other things, this should make it easier to calculate a useful cache hit ratio by excluding buffer reads via buffer access strategies. As buffer access strategies reuse buffers (and thus evict the prior buffer contents), it is normal to see reads on repeated scans of the same data.
Author: Melanie Plageman <[email protected]> Reviewed-by: Bertrand Drouvot <[email protected]> Reviewed-by: Andres Freund <[email protected]> Discussion: https://postgr.es/m/CAAKRu_beMa9Hzih40%3DXPYqhDVz6tsgUGTrhZXRo%3Dunp%2Bszb%3DUA%40mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/8aaa04b32d790da595684de58ae4fc2db96becff Modified Files -------------- doc/src/sgml/monitoring.sgml | 11 ++++++++ src/backend/catalog/system_views.sql | 1 + src/backend/storage/buffer/bufmgr.c | 38 +++++++++++----------------- src/backend/storage/buffer/localbuf.c | 11 ++------ src/backend/utils/activity/pgstat_io.c | 2 +- src/backend/utils/adt/pgstatfuncs.c | 11 +++++--- src/include/catalog/pg_proc.dat | 6 ++--- src/include/pgstat.h | 1 + src/include/storage/buf_internals.h | 2 +- src/test/regress/expected/rules.out | 3 ++- src/test/regress/expected/stats.out | 46 ++++++++++++++++++++++++++++++++-- src/test/regress/sql/stats.sql | 24 ++++++++++++++++-- 12 files changed, 109 insertions(+), 47 deletions(-)
