Yea I figured it would probably be a lot more trouble than it's worth, we don't 
live in a perfect world. Thanks

-----Original Message-----
From: David Birdsong [mailto:david.birds...@gmail.com] 
Sent: Tuesday, September 21, 2010 11:56 AM
To: Stevens, Weston J
Cc: Martin Knoblauch; ganglia-general@lists.sourceforge.net
Subject: Re: [Ganglia-general] Does Ganglia measure itself?

On Tue, Sep 21, 2010 at 11:33 AM, Stevens, Weston J 
<weston.j.stev...@boeing.com> wrote:
> Sure does thanks! I guess dig into the source code of the DSO modules to make 
> it not recognize its own cycles? Bad idea?
>
> Obviously, if Ganglia is using up considerable resources, one would want to 
> know. However, the purpose of Ganglia is to measure the performance of 
> everything else, Ganglia can skew this data. Ideally and naturally, one would 
> like to measure performance without using up any resources in doing so.
>
If you attempt do ferret out cpu statistics on a per process basis and then 
filter out gmond's use, you will almost certainly chew through many cpu cycles 
doing so.  Your machine will incur a very large user/system cpu tax and then if 
you succeed in filtering out gmond's usage, your report of the current state of 
cpu usage will be even more incorrect.  This may help to illustrate my point a 
little:
http://en.wikipedia.org/wiki/Ouroboros

> -----Original Message-----
> From: Martin Knoblauch [mailto:kn...@knobisoft.de]
> Sent: Tuesday, September 21, 2010 1:53 AM
> To: Stevens, Weston J; ganglia-general@lists.sourceforge.net
> Subject: Re: [Ganglia-general] Does Ganglia measure itself?
>
> Hi Weston,
>
>  "gmond" just looks at the low-level counters provided by the OS and has no 
> awareness about its own resource usage. So, it will collect cpu-usage 
> including its own cycles.
>
> Does this answer your question?
>
>
> Cheers
> Martin
> ------------------------------------------------------
> Martin Knoblauch
> email: k n o b i AT knobisoft DOT de
> www:   http://www.knobisoft.de
>
>
>
> ----- Original Message ----
>> From: "Stevens, Weston J" <weston.j.stev...@boeing.com>
>> To: "ganglia-general@lists.sourceforge.net"
>><ganglia-general@lists.sourceforge.net>
>> Sent: Mon, September 20, 2010 8:20:21 PM
>> Subject: [Ganglia-general] Does Ganglia measure itself?
>>
>> For instance, if gmetad and gmond are using a few percent of CPU, 
>>would this show up on the CPU usage graph? Or does it ignore itself 
>>and only count everything else?  Thanks
>>
>>
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>
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