Optimizationn questions?

Jeffrey Goldberg jeffrey at goldmark.org
Sat Mar 17 00:40:38 UTC 2007

On Mar 16, 2007, at 10:00 AM, Jerry McAllister wrote:

> On Fri, Mar 16, 2007 at 02:19:25AM +0100, Danny Pansters wrote:
>> On Friday 16 March 2007 01:04:51 Jeffrey Goldberg wrote:

>>> me, too.
>> Of course it will speed up booting but then again how much time  
>> does one spend
>> booting, compared to using the puter: not much (at least I hope so  
>> for them!)

Ah but some of us boot frequently.  We have to after each kernel  

>> If I do build my own kernel, for example to switch schedulers, I  
>> tend to toss
>> out a heap of devices that I don't have anyway. But other than a  
>> bit more
>> memory usage (which compared to the software that's run will  
>> typically be
>> minor anyhow unless you're talking embedded system or maybe not-so- 
>> embedded
>> but still of low spec special purpose boxes, like a satellite  
>> receiver box)
>> you're not going to have a slower system because your kernel  
>> happens to have
>> some built-in drivers that it doesn't use. The exception is a  
>> debug kernel of
>> course that will impact performance because it increases runtime  
>> tasks/load.
>> On a server I'd strip down the kernel, but for other reasons  
>> (avoiding any
>> unneeded complexity). On a desktop I don't care as long as thingie  
>> works.
>> YMMV of course.
> I think what he was saying is that if you already need to build a
> kernel for some other reason, then go ahead and strip out the
> unused stuff.   But, if you don't have any other reason to do it,
> it is not worth the bother to build another kernel just to strip
> it of unused stuff - that it won't make THAT much difference.
> I'd agree with that.

me, too.

I've got some linux workstations for which I've never felt the need  
to compile my own kernel.  But my FreeBSD box is a headless ITX-mini  
board that will run as a public server.  Because there was so much of  
GENERIC that I could discard for my box, it seemed to make sense.   
But I suppose the single most important factor in my decision to  
compile my own kernel is

  "Building a custom kernel is one of the most important rites of  
passage nearly
   every BSD user must endure."


Also I have m0n0wall running on a Soekris box, and someday I may want  
to customize that, so this is a good learning experience.

It's really


Jeffrey Goldberg                        http://www.goldmark.org/jeff/

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