[En-Nut-Discussion] Off-topic - Building Nut/OS fast...very fast

[Harald Kipp]

Hi Uwe,

On 7/19/2011 2:12 PM, Uwe Bonnes wrote:
> You don't tell on what system you try to build.

Sorry, Win7 64-bit. The Windows distribution requires more tools and is
more likely to fail. So I prefer to use Windows for build testing.


> Parallel builds with processors with serveral cores scales nearly linear
> even on normal disk , e.g. for the linux kernel or a wine build on linux. 
> So pure processing power is all you need first.
> 
> Does your build setup use several cores?

As explained in my other replies, this definitely speeds things up.

Nevertheless, only 3 or 4 cores are utilized up to 10 or 20% when
running make without -j. I'd expect 1 core at 90%.

On a normal disk there is a lot of stepping noise, which implied, that
this may be the reason for those lazy cores. But the SSD doesn't change
the situation much.

The "incredible performance boost of SSD" people are talking about, can
be observed only when the script creates the initial directory
structure, this is indeed a lot faster, something like 2s compared to
10s. But building takes about 2h instead of 2:15h, comparing SSD to slow
mechanical drives. So, who cares about 8s?


>     Harald> The next idea is to get faster RAM. I'm currently using cheap
> 
> Probably not worth ...

Ok, seems to the current opinion and saves me some bucks.

Thanks,

Harald