[Nottingham] SUSE Self-compiled Kernel is huge

[Michael Quaintance]

A friend of mine is stuck with using SUSE for a work project, he needs to
modify the stock kernel and so he followed the instructions from SUSE but
the resulting kernel is, in his words, gargantuan.

Anyone got any ideas on what he has done wrong? Specifically, are there any
alternate make targets he should be using instead/as well?

I've attached his own description of the problem below.

Thanks in advance.

-Michael

-------------------------------------------------------

I have an installation of SLES 11.2 on the x86_64 platform updated to the
3.0.26-0.7 kernel.

As a part of a project, I need to tweak the kernel configuration and apply
a minor patch to a few of the source files.

I did the following (based mostly on the /usr/src/linux/README.SUSE file):

Copy the source tree to my home directory:

$mkdir -p ~/builds/kernel/linux-3.0.26-0.7/src
$cd ~/builds/kernel/linux-3.0.26-0.7/src
$cp -R /usr/src/linux-3.0.26-0.7/* .

Clone the running system's configuration and then launch menuconfig to
tweak that:

$make cloneconfig
$make menuconfig

Make the following changes to the configuration:
*Change the local version string
*Enable the TCP MD5 option
*Enable IPv6 multicast routing
*Eanble IPv6 multicast multi-table support
*Enable IPv6 PIM-SM

Make my changes to the sources
Build and install and make RPMs

$make
$make modules_install
$make install
$make rpm-pkg


When I do this, the kernel I get is gargantuan compared to the binaries
provided by SUSE, even though I am supposedly using the same configuration
they used.

For comparison:

Their /lib/modules directory is about 91M, while mine is 1.8G
Their /lib/modules/kernel/drivers directory is about 60M, while mine is 1.3G
Their /lib/modules directory contains 2167 files while mine has 3772
Individual module files are much larger. For example, their
kernel/drivers/net/e1000/e1000.ko is 260K while mine is 2M.
Their initrd file is 7.1M while mine is 14M
Their vmlinuz...gz file is 4.3M while mine is 43M
The RPMs generated don't match. SUSE provided kernel-default,
kernel-default-base, kernel-devel, and linux-kernel-headers. I got only two
(kernel- and kernel-headers)
The sum total of the SUSE-provided kernel RPMs (kernel-default,
kernel-default-base, kernel-devel and linux-kernel-headers) is about 38M.
The sum of the two kernel RPMs I got is about 321M


I assume that my build is packed full of debug info and theirs isn't. Are
there alternate make targets I should be using?

If there are no magic command line parameters to give make, then it would
appear that the config file I extracted from /proc/config.gz is not the one
SUSE used to compile their kernel. Or at least not for compiling all the
modules.

What should I change in the configuration to bring my build down to a
reasonable size? There are many symbol/debug options, but I don't want to
just go randomly flipping switches trying to find the magic combination
SUSE used.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.lug.org.uk/pipermail/nottingham/attachments/20120607/104325ce/attachment.htm>