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From: Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
To: cygwin@cygwin.com
Subject: Re: [PATCH] default ps -W process start time to system boot time when inaccessible, 0, -1
Date: Sun, 24 Mar 2019 19:16:00 -0000	[thread overview]
Message-ID: <a5da8d2d-328e-f60b-3d4a-cfeffc8d7556@SystematicSw.ab.ca> (raw)
In-Reply-To: <871s2wm956.fsf@Rainer.invalid>

On 2019-03-24 12:15, Achim Gratz wrote:
> Brian Inglis writes:
>> Boot time is neither magic nor pulled out of thin air.
> No, but other than a lower limit of the process start time it has no
> correlation whatsoever to the start time of a process that I am not
> proviledged to get the start time from.
>> Checking *my* system processes using wmic queries and elevated powershell
>> scripts, the boot time is at most a few seconds off from process start times
>> from other sources.
>> I understand that other systems may run processes where that is not the case.
>> Please explain why you think this is misleadingly not useful, or where or which
>> processes have unvailable start times that are not very close to boot time.
> System processes get started and re-started all the time, as do
> processes from other users (interactive or otherwise).

System processes with more recent process start times seem to make process times
available to unelevated processes.
Do startup system processes not have this info available to unelevated processes
because of some security policy, timing, or possible race conditions with system
process and performance monitor startup?

> So again: in the case under discussion we _know_ that "0" is a bogus
> timestamp value that no process ever got started on, even if it can be
> translated to "Jan 1st 1970" if it were indeed a valid timestamp.  All
> I'm asking is that ps shows something like "N/A" instead of trying to
> print something that looks like it might be a valid time, but still
> isn't.

System startup process start times appear to not be available to unelevated
processes, so the process default value is zero.
ISTM boot time is a better, more accurate, and useful default for those processes.

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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  reply	other threads:[~2019-03-24 19:16 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20190323034522.9688-1-Brian.Inglis@SystematicSW.ab.ca>
     [not found] ` <87d0mh5x3u.fsf@Rainer.invalid>
     [not found]   ` <20190323183653.GB3471@calimero.vinschen.de>
     [not found]     ` <874l7tbfh6.fsf@Rainer.invalid>
     [not found]       ` <4dfdfce1-245d-98fe-0c49-890ba8ec8dd4@SystematicSw.ab.ca>
     [not found]         ` <874l7s65yv.fsf@Rainer.invalid>
2019-03-24 16:18           ` Brian Inglis
2019-03-24 18:15             ` Achim Gratz
2019-03-24 19:16               ` Brian Inglis [this message]
2019-03-24 19:48                 ` Achim Gratz

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