From owner-freebsd-hackers@FreeBSD.ORG  Wed Jul 14 13:34:01 2010
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Date: Wed, 14 Jul 2010 15:33:59 +0200
From: Dominic Fandrey <kamikaze@bsdforen.de>
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To: Atom Smasher <atom@smasher.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: sysctl way too slow
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On 14/07/2010 13:49, Atom Smasher wrote:
> http://smasher.org/tmp/zsh-bsd-sysctl-slow.png

Why use a screen shot here?

> is there a way to get this information that doesn't take so long?
> 
> the same info is available on linux via /sys and /proc and on comparable
> hardware, i can get the info about 100x faster.

It probably depends on your BIOS. This is the same call on my
system:
% time sysctl -n hw.acpi.battery.life hw.acpi.battery.time hw.acpi.battery.state
100
-1
0
sysctl -n hw.acpi.battery.life hw.acpi.battery.time hw.acpi.battery.state  0.00s user 0.01s system 96% cpu 0.013 total

As you can see 33 times faster than on your system.

I agree that 0.413 seconds is too long, but I don't think it makes
sense to call this value more frequently than every 30 seconds.

So I'd say it's more of an annoyance than a real problem.

Regards

-- 
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