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 From:  "Eric Shorkey" <eshorkey at commonpointservices dot com>
 To:  "Fred Weston" <fred dot weston at daytonawan dot com>, "Mitch \(WebCob\)" <mitch at webcob dot com>
 Cc:  "dave" <dave at rodrig dot com>, "Samenlia" <fhliang at 163 dot com>, <m0n0wall at lists dot m0n0 dot ch>
 Subject:  Re: [m0n0wall] about the load averages: 2.11, 0.07, 0.05
 Date:  Mon, 5 Apr 2004 02:20:47 -0400
You are correct in the assumption about "load" averages. The load is an
indication of how many active processes are waiting for their time on the
cpu. It's significance is directly based on the number of processors you
have. If you have 1 cpu, then a value of 25 means your system has some work
it needs to catch up on. If you have a load of 25, and have 2 cpu's, then
it's only half as bad. 4 cpu's means it's half as bad as if you had 2, etc.

All in all, it's a pretty useless statistic for your needs. I have more than
a few boxes that maintain around 2.0 pretty much all the time because of
background processes that are always running. It's really only useful on
machines that have around 100 people logged in at a time.

Try not to think of it as a percent of processor in use. Think of it  like
this. Anything more than 0.0 means that processes are asking for time faster
than your system can finish their requested tasks.

I'm not much of a FreeBSD user, so I can only speak for linux, but the top
command will display actual processor load in %. You can acess the necessary
information to derive processor load % by looking in /proc/stat. Here's a
like to some php code that shows you how it works:
http://www.liquidpulse.net/code/207

I think that m0n0wall should include a load % in addition to, or as a
replacement to, the current load averages that it displays in the System
section. In a firewall situation, old style load averages aren't really that
useful.

----- Original Message ----- 
From: "Fred Weston" <fred dot weston at daytonawan dot com>
To: "Mitch (WebCob)" <mitch at webcob dot com>
Cc: "dave" <dave at rodrig dot com>; "Samenlia" <fhliang at 163 dot com>;
<m0n0wall at lists dot m0n0 dot ch>
Sent: Monday, April 05, 2004 1:36 AM
Subject: Re: [m0n0wall] about the load averages: 2.11, 0.07, 0.05


> Mitch (WebCob) wrote:
>
> >That is my understanding too - BUT what I'd like to know is how that
relates
> >to performance and usability... like when does a webserver start showing
lag
> >or a vpn start dropping connections?
> >
> >I expect there are no hard and fast rules, but is there a real use to
these
> >numbers other than a realative indication of my system load?
> >
> >m/
> >
> >
> >
> I would imagine the numbers are too software specific to make any
> statements.  The only real way to tell would be to monitor the CPU usage
> and see how it affects firewall or VPN throughput.  The only problem
> there is artificially raising the CPU load in m0n0wall.  I'm not too
> familiar with FreeBSD, but I would imagine you'd have to hack some
> program in there in order to do that in a controlled manner.
>
>
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