uptime counts time spend in suspend

[Michał Gołębiowski-Owczarek]

Binary package hint: procps

According to man, amongst other things uptime shows "how long the system has been running". This is not true in the case of suspending the computer, as uptime counts the time spend in suspend as uptime time. In this way one can turn on a computer, put it to sleep for a week and then go back from suspend and uptime will show them the whole 7 days of uptime.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: procps 1:3.2.8-1ubuntu4
ProcVersionSignature: Ubuntu 2.6.32-24.43-generic 2.6.32.15+drm33.5
Uname: Linux 2.6.32-24-generic x86_64
NonfreeKernelModules: wl
Architecture: amd64
Date: Sat Sep 25 14:20:54 2010
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
SourcePackage: procps

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[rsaxvc (rsaxvc-5)]

Should we just update the documentation to reflect the program? Maybe something like "How long since the system booted" ?

[Michal Linuxak (opruz)]

Note: bug is present in Ubuntu 14.04

[Stephan (world-wide)]

This is no specific issue of procps, it just returns the value from the kernel. The kernel documents (in the source) that the value includes the time spent in suspend.

/proc/uptime gets the value from here:

https://elixir.bootlin.com/linux/v4.20.3/source/include/linux/timekeeping.h#L93

/**
 * ktime_get_boottime - Returns monotonic time since boot in ktime_t format
 *
 * This is similar to CLOCK_MONTONIC/ktime_get, but also includes the
 * time spent in suspend.
 */
static inline ktime_t ktime_get_boottime(void)
{
 return ktime_get_with_offset(TK_OFFS_BOOT);
}