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Message-ID: <be924247-c927-4fd7-8673-3cab4172aae7@dronecode.org.uk>
Date: Tue, 27 Aug 2024 16:31:39 +0100
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Subject: Re: BUG: /usr/bin/uptime always reports 0/0/0 average
To: Mark Liam Brown <brownmarkliam@gmail.com>
References: <CAN0SSYxv9A8V6gGppEid0LnjHJtY4isDUFY-ey=nbM9PaDo_8g@mail.gmail.com>
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From: Jon Turney via Cygwin <cygwin@cygwin.com>
Reply-To: Jon Turney <jon.turney@dronecode.org.uk>
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On 27/08/2024 09:21, Mark Liam Brown via Cygwin wrote:
> Greetings!
> 
> /usr/bin/uptime always reports 0/0/0 average cpu load:
> $ uptime
>   10:09:01 up 15:59,  0 user,  load average: 0.00, 0.00, 0.00
> 
> is this a known bug?

Kind of.

Due to windows API limitations, the current implementation has the 
short-coming that a process's first call to getloadavg() does not update 
the globally-maintained loadavg data.

(Because the Windows API cannot provide instantaneous cpu load, only 
over the period between two calls)

(So e.g. if you run something like top in another terminal, you'll 
suddenly see uptime return more sensible values)

See the discussion [1] for more context, and discussion of various 
approaches to fixing this, which petered out without a patch to [2]...

[1] https://cygwin.com/pipermail/cygwin-developers/2022-May/012569.html
[2] https://cygwin.com/cgit/newlib-cygwin/tree/winsup/cygwin/loadavg.cc


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