pgsql: Be smarter about age-counter overflow in formatting.c caches. - Mailing list pgsql-committers

From Tom Lane
Subject pgsql: Be smarter about age-counter overflow in formatting.c caches.
Date
Msg-id E1gCUWx-00036h-7Z@gemulon.postgresql.org
Whole thread Raw
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Be smarter about age-counter overflow in formatting.c caches.

The previous code here simply threw away whatever it knew about cache
entry ages whenever a counter overflow occurred.  Since the counter
is int width and will be bumped once per format function execution,
overflows are not really so rare as to not be worth thinking about.
Instead, let's deal with the situation by halving all the age values,
essentially rescaling the age metric.  In that way, we retain a
pretty accurate (if not quite perfect) idea of which entries are oldest.

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/2c300c680767a45450bf7afa4075095f40502dc4

Modified Files
--------------
src/backend/utils/adt/formatting.c | 70 +++++++++++++++++++++-----------------
1 file changed, 38 insertions(+), 32 deletions(-)


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