i.MX6QuadPlus - booting with roofts on ramdisk

[can_tuncbilek]

Hi,

   I want to reduce the booting time. I am using imx6QP with Yocto Morty and kernel version is 4.9.11. To reduce booting time, I created ramdisk with following change in my conf/local.conf:

INITRAMFS_IMAGE = "esomimx6-initramfs"

INITRAMFS_IMAGE_BUNDLE = "1"

I obtain a cpio.gz file but I cannot boot the system. Do I need to change u-boot, environmental variables or something else? 

[can_tuncbilek]

Hi weidong.sun,

Thank you very much for the prompt reply.

I want to reduce system boot time. Is it possible to run the file system in RAM? If yes, does this change reduce booting time?

Best Regards,

Can

[weidong_sun]

Hi Can,

>>Is it possible to run the file system in RAM?

yes, it is possibe.

>>If yes, does this change reduce booting time?

yes,it does. because it is very small.

Actually, ramdisk is also a kind of rootfs, whose usage is the same as that of common one.

BUT you know there are few funtions in it.

So the bettery way to reduce rootfs size on the basis of core-image-minimum.

Hope above information is helpful for you.

Have a nice day!

B.R,

Weidong

[can_tuncbilek]

Hi weidong.sun‌,

I reduced the size of the root files using 'core-image-minimal-x11'. I am using a simple camera application on imx6qp. How can I run the root file system in ram to further speed up the boot time?

Best Regards,

Can

[weidong_sun]

Hi Can,

   According to your descriptions, my advice is :
1. Try to reduce u-boot & kernel image size.
it can also improve booting speed.
2. try to check if you can capture camera image on your current rootfs.
--if yes, it indicates libs for camera is no problem, then continue to do further reduction.

[comment]

No matter how you reduce image, system booting needs time, which is unchangable, so you should evaluate how much time you can accept for you application.

Hope above advice is helpful for you!

Have a nice day!

B.R,

Weidong

[weidong_sun]

Hi Can,

cpio.gz file is for MFG Tools OS Firmware, see below,please!

L4.9.11_1.0.0-ga_mfg-tools\mfgtools\Profiles\Linux\OS Firmware\firmware

If you want rootfs with smalle size, you can select the ways below:

1. Compile minimal rootfs

or

2. reduce the size of rootfs

Before compiling rootfs in yocto, you can specify those packages you don't want.

In build/conf/local.conf, like below:

PACKAGE_EXCLUDE = "package_name package_name package_name ..."

Hope above information is helpful for you!

Have a nice day!

B.R,

Weidong