[U-Boot] During boot is U-Boot doing its jobs sequentially or in parallel?

[Wolfgang Denk]

Dear Frank,

In message <5328485C020000460004BFD4 at gwia2.rz.hs-offenburg.de> you wrote:
>
> >Q1: why are you using so old software?
> 
> Because of some patches it's a big job to switch to a newer one.

Well, you cut yourself off from all nice features present in more
recent versions...

> >Q2: Do you actually have a plan for your optimizations, or are you
>     >just poking around at random?
>
> It's not poking around, the aim is to see what effects do some
> options really ("atomically") have. I'm doing many measurements and
> always compared with a Buildroot defconfig that takes time around
> 10.6 s time from Bootloader to Userland.

I'm sorry, but I do call this poking around.  When doing
optimizations, you should always start with measuring the current
state first.  Only when you klnow exactly hoiw long each step of the
boot process takes you can determine where it makes sense to spend
efforts on the optimization.  Saving 50% of the time sounds great, but
it means nothing if it's for a step that contributes only 1% to the
total boot time.

Best regards,

Wolfgang Denk

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