am335x boot time optimization

Matti Kaasinen

Hi!
I found this (skydrive.live.com/redir article from TI training discussing boot time optimization. There were two details I probably got wrong or that I have found opposite way.

- Use faster boot media

NOR/NAND vs. MMC/USB

I understood above that booting from NOR or NAND would be faster than from MMC or USB

I have measured booting from SD memory around 10 seconds faster than booting from NAND flash. If this is correct notice would it also mean that booting from eMMC would be this 10 seconds faster?

- Use systemd for parallel initialzation

This I have also measured taking about 10 seconds more time than booting same configuration with sysv init.

My kernel version is 3.18

Would anyone have better understanding/experience about these issues?

Cheers,

Matti

over 8 years ago

0 Shankari G over 8 years ago

TI__Mastermind 43955 points

Hi Matti,
Refer to the following TI wiki pages.
processors.wiki.ti.com/.../Boot_Time_Optimization
processors.wiki.ti.com/.../Optimize_Linux_Boot_Time
processors.wiki.ti.com/.../Sitara_Linux_Training:_Boot_Time_Reduction
processors.wiki.ti.com/.../All_This_For_1_Second_Boot
processors.wiki.ti.com/.../Sitara_Linux_Training

0 Matti Kaasinen over 8 years ago in reply to Shankari G

Intellectual 660 points

Hi Shankari,

Thank you for these interesting links. So, my first point was kind of (perhaps) answered in Sitara Linux Training module: "In this lab the SD card was chosen because it has good throughput, particularly in u-boot in the which the NAND performance is not currently optimized". So, SD memory card is perhaps considered slightly faster than NAND. Would it not be the same with eMMC?

What about systemd? It was not touched at all in these wiki pages.

Thanks,

Matti

0 Shankari G over 8 years ago in reply to Matti Kaasinen

TI__Mastermind 43955 points

Hi Matti,
Regarding systemd, you can refer to the following link.
freedesktop.org/.../

0 Matti Kaasinen over 8 years ago in reply to Shankari G

Intellectual 660 points

Hi Shankari!

Thank you for this link. Optimizations it suggests seem pretty much like desktop - Fedora - optimizations. Very few of them seem like embedded stuff. I have tried any optimizations so far. However, I made test boots with three set-ups. Basically same sw was booted in every time except in SystemD case I did not have my own applications at all. Main applications in these configurations are Apache, OpenSSH and ntp daemon. Boot strapping favors NAND flash, so MLO is always coming from NAND.

1) Booting from SD card/sysv: 22 seconds
2) Booting from SD card/SystemD: 33 seconds
3) Booting from NAND/sysv: 34 seconds

It is very hard for me to believe that SystemD is faster. It is true that I have not done any optimizations but so it is with sysv init. Basically both are installed with Yocto recipes.

Regards,
Matti

Processors

Processors forum

am335x boot time optimization