revisit: turning some of the "always used" modules to built-in

[Arjan van de Ven]

On Mon, 23 Jun 2008 10:48:43 -0400 (EDT)
Joshua Baker-LePain <jlb17 at duke.edu> wrote:

> On Sun, 22 Jun 2008 at 11:42am, Arjan van de Ven wrote
> 
> > Category 3: popular/very common and makes the system more robust
> > ----------------------------------------------------------------
> > Rationale: having these built in makes the system more robust, also
> >           in case of failure
> > - ahci (default storage for all new systems; means that there the
> > system always has the / device driver)
> 
> This isn't the default for all new systems -- lots of folks boot off 
> SCSI/RAID.

... and then have the cdrom hang of ahci.

> 
> > - cpufreq_ondemand (means the cpu can slow down for power/thermal)
> > - acpi_cpufreq (means the cpu can slow down for power/thermal)
> 
> Not everybody wants this -- think HPC.

not everyone wants the policy on by default.. that's a whole different
discussion. But even HPC wants thermal protection etc enabled.

> 
> > Category 4: VERY popular
> > ------------------------
> > Rationale: pretty much always loaded in default installs
> > - snd_seq_dummy, snd_seq, snd_seq_device,
> >  snd_pcm, snd_timer, snd_page_alloc, snd
> 
> Completely useless and unwanted on servers/HPC nodes.

yet tends to get loaded ;)

> 
> It seems that there's an assumption here that Fedora = desktop.
> While there's obviously a lot of that, I've seen it on a fair number
> of servers and it is a great fit for HPC nodes.

No that wasn't my assumption actually. My assumption was that those
things are either always loaded, extremely likely loaded by default or
for robustness (say AHCI). I realize it won't hit 100% but... the worst
case downside is a tiny bit of wasted memory. Yawn.
With the upsides I mentioned in my mail.. for me it's worth the
tradeoff for at least almost all of these.

> 



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