pgsql: doc: Mention pg_stat_force_next_flush()

doc: Mention pg_stat_force_next_flush()

pg_stat_force_next_flush() has primarily been used in in-core tests to
force cumulative statistics to be flushed at the end of a transaction
without waiting for the PGSTAT_MIN_INTERVAL throttle, to speed up
things.

It is also useful in tests outside the core tree. Spoiler: I have used
it myself for some out-of-core work for the same reason as the in-core
tests, and would have unlikely known about it without my work on the
core code.

Author: Sami Imseih <samimseih(dot)pg(at)gmail(dot)com>
Discussion: https://postgr.es/m/aqEONVuLhgBiqHW6@paquier.xyz

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c8985a09b7b52519f794c433e5f8f7311a77a2fc

Modified Files
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doc/src/sgml/monitoring.sgml | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)