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Message-ID: <402A4AE2.8010506@algroup.co.uk>
Date: Wed, 11 Feb 2004 15:31:46 +0000
From: Ben Laurie <ben@algroup.co.uk>
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To: Bill Stoddard <bill@wstoddard.com>
Cc: dev@apr.apache.org
Subject: Re: routines for fetching load average?
References: <4027F709.2090405@Golux.Com> <402A2480.1080705@Golux.Com>
 <402A354B.1050102@wstoddard.com>
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Bill Stoddard wrote:

> Rodent of Unusual Size wrote:
> 
>> Rodent of Unusual Size wrote:
>>
>>
>>> would anyone have any thoughts about the idea of adding an
>>> api to obtain the system load average?  i ask because i need
>>> it for an httpd module i'm writing, and i've now got code
>>> for linux, freebsd, os x, sunos, and t64u..
>>
>>
>>
>> no thoughts, uh.
> 
> 
> load average is nice but it seems rather specialized and it doesn't 
> really fit anywhere in apr[-util] that I see.  load average is one 
> performance metric; I can see where it might be useful to have a common 
> interface for collecting all sorts of performance metrics. For example, 
> if Apache is being used as a load balancer, you could collect 
> performance state metrics from the servers being load balanced, feed 
> that info back to the apache load balancer (on an HTTP response header 
> field, via a special purpose HTTP POST request or out of band) and use 
> it in your load balancing/routing algorithms.

Errr - mod_backhand?

>  I just don't see that this has a place in apr or apr-util. Maybe a new subproject, apr-perf?

I don't follow your logic - APR is supposed to make the interface to the 
system portable. Load average is an interface to the system. Why does it 
need to "fit"? All it needs is support on enough platforms to be 
considered common and someone who wants to use it.

Sounds like we have both.

Are you seriously suggesting APR should only support things that are 
obvious extensions of what it already does?

Cheers,

Ben.

-- 
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"There is no limit to what a man can do or how far he can go if he
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