Add a Digital Clock plasmoid to the panel and enable seconds display. Run "xclock -digital -update 1" and compare the two clocks. xclock will advance the seconds precisely when the system clock ticks, but odds on the Digital Clock will be delayed by up to a second. The exact offset fluctuates, and is different each time seconds display is disabled and then re-enabled. This also affects the time at which the Digital Clock advances minutes. xclock makes sure it updates on time in an elegant way: subtract the current time from the time the next update is due, and wait that number of microseconds. See xclock/Clock.c:waittime() for details. Digital Clock doesn't seem to do this. It seems to wait to be painted, and then prints the current time accurate to the second. That will always create this bias. Qt::formatTime() does seem to support milliseconds using the .zzz expression, but scheduling updates may be more challenging. If the API allows it, Digital Clock should be modified to request updates at the correct time, not just let them happen.
> subtract the current time from the time the next update is due Plasma data engine polling works similarly, trying to batch upcoming updates and schedule them e.g. on the full minute or second but it allows some deviation in order to reduce wakeups when there's multiple dataengines polling.
Can confirm.
I can reliably reproduce this under Plasma 5.25.4 and 5.24.6 after waking up the monitor from sleep. In that case, the clock in either Plasma or Latte Dock ends up being late by about a second, and the second-skipping behavior at zero seconds as described in bug #436796 occurs as a result. The only workaround is to restart plasmashell/Latte multiple times until the clock is no longer running a full second late. It's frustrating that this is an incredibly difficult bug to pinpoint, which explains why it hasn't been fixed for so long. SYSTEM INFORMATION Operating System: Manjaro Linux KDE Plasma Version: 5.25.4 KDE Frameworks Version: 5.96.0 Qt Version: 5.15.5 Kernel Version: 5.18.16-1-MANJARO (64-bit) Graphics Platform: X11 Processors: 12 × AMD Ryzen 5 1600 Six-Core Processor Memory: 31.3 GiB of RAM Graphics Processor: AMD Radeon RX 570 Series
any updates? bug still there on plasma 5.27
*** Bug 475962 has been marked as a duplicate of this bug. ***
*** Bug 477082 has been marked as a duplicate of this bug. ***
still exist on plasma 6.0.2