Critique of NO_HZ and thoughts about power savings (Re: 2.6.21)

[Oleg Verych <olecom@flower.upol.cz>]

* From: Folkert van Heusden
* Date: Wed, 30 May 2007 17:18:40 +0200
* Organization: www.unixexpert.nl
>
>> > > > Please consider upgrading to 2.6.21 or backporting the NO_HZ
>> > > > functionality as it reduces powerusage of a processor and thus saves the
>> > > > environment.
>> > > since long enabled and is in sid.
>> > Are you sure?
>> Yes. But only available for i386.
>
> Ok, thanks.
>

Too much fallout (for .21 release) for useless feature even not for most
modern hardware, e.g. AMD64.

Let me speak a little bit about one great misunderstanding of how
things are actually work regarding electricity.

I think you can realize, if i will point you, that DRAM, VGA, HDD are
much more power hungry beasts. That for desktops. For servers as for
computers with permanent Internet link NETCARD is another addition.
Because even services-empty machine will listen for stupid misconfigured
OS' broadcasts, port-scans, (in case of ssh) huge amount of cracking
attempts.

The major point about electricity is, that it cannot be accumulated in
amounts comparable to consuming. With fact, that power plants cannot stop
producing energy in the night time all this lead to one very sad
conclusion:

We are paying even for that electricity, that we do not actually
consume. This is economical trick. where you were brain-washed about
power-saving, while prices are still growing.

Difference in day/night power might be compensated just for useless
rotating of motors. But it seems better to useless light streets all
night long.

One big exception is day light savings. Because if you lower power
consumption for relatively big amount of users for big period, power
plants may low producing power.

Not final truth, but still.

> Folkert van Heusden
>
> -- 
____