a lean linux distribution

silvermangb · n00b Joined: 21 May 2016 Posts: 4

I am learning gentoo because I want to create a very lean distribution, minimizing the total number of bytes for all files before installing my application software.

After building gentoo there are hundreds of megabytes of files I need to eliminate, such as the portage package manager, python2 and python3, etc. The software on these machines will never need to update or upgrade, they will have all software completely reinstalled.

What procedures are there to remove unnecessary files?

khayyam · Posted: Sat May 21, 2016 11:38 pm Post subject:

silvermangb ...

if you want "very lean" then perhaps gentoo isn't the best choice, something like Alpine or Aboriginal would be better suited. That said, you should look at '--root=/path' and '--root-deps=rdeps' (man emerge), and INSTALL_MASK, FEATURES="nodoc noman noinfo", in the portage and make.conf manpages. You might also think about building from either the uClibc or musl stage3.

HTH & best ... khay

silvermangb · n00b Joined: 21 May 2016 Posts: 4

I added

FEATURES="sandbox nodoc noman noinfo"

to make.conf, but, it did make the documents, manual, and info

NeddySeagoon · Posted: Sun May 22, 2016 6:31 pm Post subject:

silvermangb,

Yes, they are still made ... then they are thrown away. Its a feature.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

silvermangb · n00b Joined: 21 May 2016 Posts: 4

Ok, but when are they thrown away? they were still there after rebooting to the new installation.

NeddySeagoon · Posted: Sun May 22, 2016 6:34 pm Post subject:

silvermangb,

They are thrown away at install time. Those FEATURE changes will not affect packages that are already installed.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

khayyam · Posted: Sun May 22, 2016 7:34 pm Post subject:

silvermangb ...

I was pointing out how you might build a "very lean" install, so, from the start of the build. This you would do by firstly using a suitable stage3, or build, and using '--root=/path' and '--root-deps=rdeps' so that the target (the path stipulated by --root) would only be runtime requirements (which is all you need given the install won't be updated ... no build time dependencies are required). Using FEATURES, INSTALL_MASK, etc, you could further slim it down, but as you're not going to be using any method to manage the install you can as well remove these paths by hand:

silvermangb · n00b Joined: 21 May 2016 Posts: 4

For my current project, less than 500MB of system and application files would be lean enough. I took a trial run at using the root, say --root=/target-root, and root-deps command line parameters on emerge and it looks as though that could do the trick. But, it looks like, at some point, I would have to chroot to target-root to build and install the kernel and grub. Ot takes a very long time by trial and error to find out what works, so, I ask, can I emerge everything to target-root and chroot into it after the emerges are done?

Thanks

khayyam · Posted: Sun May 22, 2016 11:17 pm Post subject:

NeddySeagoon · Posted: Mon May 23, 2016 11:45 am Post subject:

silvermangb,

It sounds as if you are doing what the embeded project was designed for, except you do not need a cross compiler.
It may be useful.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

szatox · Advocate Joined: 27 Aug 2013 Posts: 3619

NeddySeagoon · Posted: Tue May 24, 2016 6:52 pm Post subject:

szatox,

szatox · Advocate Joined: 27 Aug 2013 Posts: 3619

Yes Neddy, AFAIK it hardcodes location of the next stage loaded by the piece located in MBR, so you have to be careful when you play with partition layout. However, if you're going to move it with dd, it's not an installation to the target device.
Good news is, if you actually have to move that build with dd, all it takes is putting the rest of grub on the first partition. It can be either root or (better) separate boot partition. The last partition can be expanded after writing image to a disk, and additional partitions may be created afterwards, it doesn't matter. Don't touch stage files and you will be fine.
Oh, and this tool comes in handy if things go very wrong: LINK I'm a bit disappointed it grew that fat over time. I can remember running it from a floppy :roll: