Kernel Start-up Time

[caglarakyuz@gmail.com (Caglar Akyuz)]

On Tuesday 19 January 2010 01:04:04 pm Bahadir Balban wrote:
> Caglar Akyuz wrote:
> > Hello,
> >
> > While measuring Linux start-up time, I see that printing version string
> > in "start_kernel" takes ~1.3 seconds. I guess this is the time between
> > from "bootloader jumping to uImage" and "printing version string in
> > generic start_kernel code".
> >
> > Thanks,
> > Caglar
> >
> > _____________________________________________________________________
> >
> > [    4.700896] Starting kernel ...
> > [    4.702971]
> > [    5.966039] [    0.000000] Linux version
> > 2.6.30-davinci1-06079-g4e73fae-
> 
> Hi Caglar,
> 
> This sounds like the kernel decompression is taking time. Have you tried
> booting an uncompressed kernel? See if you can print on physical uart
> address from files under arch/arm/boot/compressed
> 
> Thanks,
> 

Hi,

My image was uncompressed already. However, I was fooled by the printk delays. 
Learning proper use of early printk solved the issue.

Thanks,
Caglar