+++ This bug was initially created as a clone of Bug #1004416 +++
Description of problem:
Hi, then problem is based on
I've tried to use time to measure problem, but time itself is not able to deal with time shift and show incorrent result
Steps to Reproduce:
# time sleep $CONST&
# sleep $W
# date -s "now - 1 minute"
# wait $BPID
# date -s "now + 1 minute"
# let DIFF=(`date +%s -d "$DNEW"` - `date +%s -d "$DOLD"`)
# echo $(($DIFF+$W)) == $CONST
time difference is 70 sec
but time show:
--- Additional comment from Petr Pisar on 2013-09-09 12:24:20 GMT ---
Despite you use built-in `time', there is the same problem with GNU time.
I also think that time should measure monotonic (-alike) time not to get influenced by shifts in system clock.
CLOCK_MONOTONIC -- suffers from NTP time adjustment.
CLOCK_MONOTONIC_RAW -- uses real hardware clock, I worry about precision and access permission for non-root users.
CLOCK_BOOTTIME -- includes time elapsed in suspension but suffers from NTP time adjustment. Is it worth?
I guess the CLOCK_MONOTONIC_RAW is the most appropriate.
--- Additional comment from Petr Pisar on 2014-10-21 13:15:50 GMT ---
Upstream agreed to use clock_gettime(CLOCK_MONOTONIC) for measuring the "real" value.
Patches posted to upstream <http://lists.gnu.org/archive/html/bug-gnu-utils/2016-12/msg00000.html>, but upstream seems dead.
We do not plan to fix this issue in RHEL-7. If you are affected, please escalate it to Red Hat support with reference to this bug report.