Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Kernel compilation
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware
View previous topic :: View next topic  
Author Message
ttre
n00b
n00b


Joined: 04 Aug 2016
Posts: 29

PostPosted: Thu Mar 23, 2017 8:11 pm    Post subject: Kernel compilation Reply with quote

I have questions about kernel.

Last kernel that I compiled was 4.9.6, and It was last week and it was first time since I have installed gentoo in spring 2016.
Now I see that emerge took gentoo sources 4.9.16, so I probably need to compile again.

1. How often is released new kernel version ?
2. Do I need to compile new kernel always ?
3. My size of kernel is 5282832 is it too big ?
4. I have netbook 1,6 GHz - one core and my kernel compile 10 hours - is not too long ?
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43758
Location: 56N 3W

PostPosted: Thu Mar 23, 2017 8:41 pm    Post subject: Reply with quote

ttre,

You should update your kernel once every minor release. That's 4.x to 4.x+1. Its about every 8 weeks.
Consider doing security updates as they happen, if you need the fixes.

5.2Mb is only part of your kernel. Thats the binary with all the built in modules.
The loadable modules are in /lib/modules. They are a part of the kernel build.

You can save kernel compile time by removing things you will never need, in the menuconfig stage.
How you do that and what you can remove, depends on your hardware and how you build your kernel.

I have a netbook like that too.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
ttre
n00b
n00b


Joined: 04 Aug 2016
Posts: 29

PostPosted: Thu Mar 23, 2017 8:53 pm    Post subject: Reply with quote

I noticed that a lot of modules installation took a lot of time.

I wonder if there are parts in menuconfig level that I do not need in normal desktop using or if it need to be individual approach.
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43758
Location: 56N 3W

PostPosted: Thu Mar 23, 2017 9:01 pm    Post subject: Reply with quote

ttre,

The kernel can almost drive all of the hardware made in the last 20 years, much of which is now forgotten.
You probably don't have much of that in your netbook.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
nativemad
Developer
Developer


Joined: 30 Aug 2004
Posts: 911
Location: Switzerland

PostPosted: Thu Mar 23, 2017 9:54 pm    Post subject: Reply with quote

Hey ttre,
You can actually disable most of the drivers and only enable what you need...
The good thing is that the kernel is quite good in finding out what it needs to be built/rebuilt after a config change!
So if you compile the kernel once and change the config, the next run will be quite quick as it only compiles the changes.
This is the default with manual compilation and can be achieved with genkernel by adding --no-clean.
So don't be afraid of disabling stuff as long as you keep a rescue kernel that at least boots (either a different version or one with everything needed such as the disk built in and not as module... because modules get rewritten within the same version! 8)

Of course, also little core changes might affect all modules and take quite long to compile therefore..................

HTH, cheers
_________________
Power to the people!
Back to top
View user's profile Send private message
ttre
n00b
n00b


Joined: 04 Aug 2016
Posts: 29

PostPosted: Fri Mar 24, 2017 4:27 pm    Post subject: Reply with quote

nativemad wrote:
Hey ttre,
You can actually disable most of the drivers and only enable what you need...
The good thing is that the kernel is quite good in finding out what it needs to be built/rebuilt after a config change!
So if you compile the kernel once and change the config, the next run will be quite quick as it only compiles the changes.
This is the default with manual compilation and can be achieved with genkernel by adding --no-clean.
So don't be afraid of disabling stuff as long as you keep a rescue kernel that at least boots (either a different version or one with everything needed such as the disk built in and not as module... because modules get rewritten within the same version! 8)

Of course, also little core changes might affect all modules and take quite long to compile therefore..................

HTH, cheers


ok, my last compilation seemed:
Code:

zcat /proc/config.gz > /usr/src/linux/.config

cd /usr/src/linux
cp .config ~/kernel-config-`uname -r`
make oldconfig && make && make modules_install install
genkernel --install initramfs
grub-mkconfig -o /boot/grub/grub.cfg
emerge --ask @module-rebuild


I think that using genkernel with --no-clean option it should be a little differently.
Back to top
View user's profile Send private message
nativemad
Developer
Developer


Joined: 30 Aug 2004
Posts: 911
Location: Switzerland

PostPosted: Sat Mar 25, 2017 4:00 pm    Post subject: Reply with quote

Quote:
genkernel --install initramfs

No, you seem to use genkernel only to create the initramfsthat way!
Quote:
make oldconfig && make && make modules_install install

This is what takes ages, and there it shouldn't clear a previous compile run...
You can customize the kernel by running "make menuconfig" before the actual "make".
_________________
Power to the people!
Back to top
View user's profile Send private message
ttre
n00b
n00b


Joined: 04 Aug 2016
Posts: 29

PostPosted: Sat Mar 25, 2017 4:18 pm    Post subject: Reply with quote

nativemad wrote:

No, you seem to use genkernel only to create the initramfsthat way!


ok, I followed https://wiki.gentoo.org/wiki/Kernel/Upgrade
there is nothing about genkernel to use.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Kernel & Hardware All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum