postgresql/src
Tom Lane 171c457cd0 Fix and simplify some usages of TimestampDifference().
Introduce TimestampDifferenceMilliseconds() to simplify callers
that would rather have the difference in milliseconds, instead of
the select()-oriented seconds-and-microseconds format.  This gets
rid of at least one integer division per call, and it eliminates
some apparently-easy-to-mess-up arithmetic.

Two of these call sites were in fact wrong:

* pg_prewarm's autoprewarm_main() forgot to multiply the seconds
by 1000, thus ending up with a delay 1000X shorter than intended.
That doesn't quite make it a busy-wait, but close.

* postgres_fdw's pgfdw_get_cleanup_result() thought it needed to compute
microseconds not milliseconds, thus ending up with a delay 1000X longer
than intended.  Somebody along the way had noticed this problem but
misdiagnosed the cause, and imposed an ad-hoc 60-second limit rather
than fixing the units.  This was relatively harmless in context, because
we don't care that much about exactly how long this delay is; still,
it's wrong.

There are a few more callers of TimestampDifference() that don't
have a direct need for seconds-and-microseconds, but can't use
TimestampDifferenceMilliseconds() either because they do need
microsecond precision or because they might possibly deal with
intervals long enough to overflow 32-bit milliseconds.  It might be
worth inventing another API to improve that, but that seems outside
the scope of this patch; so those callers are untouched here.

Given the fact that we are fixing some bugs, and the likelihood
that future patches might want to back-patch code that uses this
new API, back-patch to all supported branches.

Alexey Kondratov and Tom Lane

Discussion: https://postgr.es/m/3b1c053a21c07c1ed5e00be3b2b855ef@postgrespro.ru
2020-11-10 22:51:55 -05:00
..
backend Fix and simplify some usages of TimestampDifference(). 2020-11-10 22:51:55 -05:00
bin Ignore attempts to \gset into specially treated variables. 2020-11-09 07:32:13 -08:00
common
fe_utils
include Fix and simplify some usages of TimestampDifference(). 2020-11-10 22:51:55 -05:00
interfaces Stamp 12.5. 2020-11-09 17:26:33 -05:00
makefiles
pl Translation updates 2020-11-09 12:36:44 +01:00
port Stamp 12.5. 2020-11-09 17:26:33 -05:00
template Makefile comment: remove reference to tools/thread/thread_test 2020-10-27 14:00:48 -04:00
test Work around cross-version-upgrade issues created by commit 9e38c2bb5. 2020-11-10 18:32:36 -05:00
timezone Update time zone data files to tzdata release 2020d. 2020-10-22 21:24:07 -04:00
tools Sync our copy of the timezone library with IANA release tzcode2020c. 2020-10-16 21:40:16 -04:00
tutorial
.gitignore
DEVELOPERS
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Makefile.global.in
Makefile.shlib
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