Optimizationn questions?

Danny Pansters danny at ricin.com
Fri Mar 16 01:19:42 UTC 2007


On Friday 16 March 2007 01:04:51 Jeffrey Goldberg wrote:
> On Mar 15, 2007, at 5:21 PM, Jorn Argelo wrote:
> > youshi10 at u.washington.edu wrote:
> >> On Thu, 15 Mar 2007, Danny Pansters wrote:
> >>      I know that this has been discussed a few times before, but
> >> IMO running a slightly stripped down kernel (i.e. custom, not
> >> GENERIC) actually proves to be helpful in increasing boot times
> >> (if options were added statically) and compile times if [(# of
> >> options added) < (# of options in GENERIC)].
> >
> > I can confirm this too. I noticed on both desktop and servers the
> > boot time can be decreased by stripping the kernel configuration of
> > stuff you don't need. I don't have any hard facts to prove this but
> > this is what my personal experience is.
>
> 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!)

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.

Dan


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