Android kernel size

[Michal Suchanek]

Hello,

I tried to build an android kernel with a more complete config and
currently the size is

kernel image 4.3M

modules 224M (down from 258M of the general Linux config)

most obvious offenders:

drivers/media 60M
out of that:
drivers/media/video 25M
drivers/media/video/sun4i_csi 2.8M
drivers/media/radio 2.7M
drivers/media/rc 4.9M
drivers/media/dvb 25M
drivers/media/common/tuners 3.3M

drivers/net/wireless 71M
drivers/net/wimax 3.2M
drivers/net/usb 5.2M
drivers/usb/serial 8.8M

drivers/staging 13M

drivers/hid 5.4M
drivers/input 11M

sound/usb 2.9M

drivers/scsi 4.3M
drivers/md 4.2M

drivers/rtc 3.4M

Removing some more drivers without losing much functionality is
possible but overall around 130M of drivers are for features people
are repeatedly asking about.

Thanks

Michal

[Roman Mamedov]

On Tue, 4 Jun 2013 11:42:11 +0200
Michal Suchanek <hram...@gmail.com> wrote:

> Hello,
>
> I tried to build an android kernel with a more complete config and
> currently the size is
>
> kernel image 4.3M
>
> modules 224M (down from 258M of the general Linux config)
>

Check if you have CONFIG_DEBUG_INFO enabled. It causes much larger binary
modules to be generated.

Comparing a random one with mine:

> most obvious offenders:
...
> drivers/media/dvb 25M

# find /lib/modules/3.4.29-20130418.1754-s-rm5+/kernel/drivers/media/dvb/ -type f | wc -l
88

# du -hsc /lib/modules/3.4.29-20130418.1754-s-rm5+/kernel/drivers/media/dvb/
2.0M /lib/modules/3.4.29-20130418.1754-s-rm5+/kernel/drivers/media/dvb/
2.0M total

--
With respect,
Roman

[Hans de Goede]

Hi,

On 06/04/2013 11:54 AM, Roman Mamedov wrote:
> On Tue, 4 Jun 2013 11:42:11 +0200
> Michal Suchanek <hram...@gmail.com> wrote:
>
>> Hello,
>>
>> I tried to build an android kernel with a more complete config and
>> currently the size is
>>
>> kernel image 4.3M
>>
>> modules 224M (down from 258M of the general Linux config)
>>
>
> Check if you have CONFIG_DEBUG_INFO enabled. It causes much larger binary
> modules to be generated.

Yes, you likely have CONFIG_DEBUG_INFO enabled, besides disabling it and
recompiling everything, you can also do:

find <path-to-modules-dir> -name "*.ko" -exec arm-linux-gnu-strip --strip-debug '{}' \;

This assumes you're doing the stripping on your build machine, not on the
actual Axx itself.

Regards,

Hans

[Michal Suchanek]

Yes, I have debug info enabled.

Is it reasonable to build android images with debug disabled by default?

Thanks

Michal