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* Buggy idle time reported in /proc/uptime for SMP systems?
@ 2007-10-18 16:25 Srivatsa Vaddagiri
  2007-10-18 19:12 ` Srivatsa Vaddagiri
  0 siblings, 1 reply; 2+ messages in thread
From: Srivatsa Vaddagiri @ 2007-10-18 16:25 UTC (permalink / raw)
  To: torvalds, akpm, Ingo Molnar; +Cc: linux-kernel, pbadari, dhaval

The idle time reported in /proc/uptime (2nd field) seems to be the idle
time of only CPU0. Shouldn't it reflect the total idle time on a SMP system? 
Do folks agree that it is a bug that needs to be fixed? If so, will send
a patch ...

Fyi, I see patches submitted to fix this way back in 2001
[http://lkml.org/lkml/2001/3/17/55], but don't think they made in ..

-- 
Regards,
vatsa

^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: Buggy idle time reported in /proc/uptime for SMP systems?
  2007-10-18 16:25 Buggy idle time reported in /proc/uptime for SMP systems? Srivatsa Vaddagiri
@ 2007-10-18 19:12 ` Srivatsa Vaddagiri
  0 siblings, 0 replies; 2+ messages in thread
From: Srivatsa Vaddagiri @ 2007-10-18 19:12 UTC (permalink / raw)
  To: torvalds, akpm, Ingo Molnar; +Cc: linux-kernel, pbadari, dhaval

On Thu, Oct 18, 2007 at 09:55:13PM +0530, Srivatsa Vaddagiri wrote:
> The idle time reported in /proc/uptime (2nd field) seems to be the idle
> time of only CPU0. Shouldn't it reflect the total idle time on a SMP system? 
> Do folks agree that it is a bug that needs to be fixed? If so, will send
> a patch ...

On further reflection, it doesn't sound buggy. Reporting idle time across all
cpus in /proc/uptime will cause idle time > uptime, which will be odd. I
guess if anyone wants strict idle time from all cpus, they can always
look at /proc/stat.

> Fyi, I see patches submitted to fix this way back in 2001
> [http://lkml.org/lkml/2001/3/17/55], but don't think they made in ..

-- 
Regards,
vatsa

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2007-10-18 19:04 UTC | newest]

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