Wastage of memory due to multiple compiled kernels copies .

Hi there,

If you have installed them, you just need to delete them from these paths:

/lib/modules/$KVER
/boot/vmlinuz-$KVER
/boot/initr*-$KVER

This is how I do it on Arch Linux using fish (I just keep my most recent build and the linux package kernel):

set -l old_imgs (ls /lib/modules | grep -Ev "^$(uname -r)\$|arch" | sort)
for old_img in $old_imgs
    echo Purging v$old_img...
    sudo rm -rI /usr/lib/modules/$old_img \
        /boot/vmlinuz-$old_img \
        /boot/initramfs-$old_img.img
end
sudo grub-mkconfig -o /boot/grub/grub.cfg

If you are working with different Linux trees, you can reduce disk usage by adding each tree as a new remote and fetching, instead of cloning the entire tree again. This roughly minimizes the size of each tree (normally 5–6 GB) to around ~1.5 GB per new remote. Unfortunately, there's no way around needing at least 30~40 GB for kernel development if you are actively working on different subsystems with different trees. Especially if you are keeping your different builds.

@hannelotta said:
If you're using Ubuntu or Debian, there are apt-get commands to remove kernel versions (purge). It might be a better option than removing folder contents manually. Make sure you're not removing a kernel you are currently using.

Note that apt can't detect custom kernels/initramfs images installed using /sbin/installkernel (i.e., via make install). It only manages kernels installed from the repositories, and removes them based on the file list found in:
/var/lib/dpkg/info/<packagename>.list