On Thu, Nov 24, 2022 at 10:26:22AM +0800, Coiby Xu wrote:
On Thu, Nov 24, 2022 at 10:12:14AM +0800, Coiby Xu wrote:
>On Tue, Nov 22, 2022 at 09:24:24AM +0800, Tao Liu wrote:
>>On Mon, Nov 21, 2022 at 8:24 PM Hari Bathini <hbathini(a)linux.ibm.com>
>>>If available, use 'zstd' compression method to optimize the size of
>>>the initrd built with fadump support. Also, 'squash+zstd' is not
>>>preferred because more disk space is consumed with 'squash+zstd' due
>>>to the additional binaries needed for fadump with squash case.
>>>Signed-off-by: Hari Bathini <hbathini(a)linux.ibm.com>
>>>Changes in v2:
>>>* Updated changelog with why 'zstd' is used for fadump.
>>Thanks for the update, the patch looks good to me.
>>Acked-by: Tao Liu <ltao(a)redhat.com>
>When trying to learn how squash affects the memory requirement of kdump,
>I notice currently for both F36 and F37, the initramfs is no longer
> [root@ci-vm-10-0-137-168 t]# file
> /boot/initramfs-6.1.0-0.rc6.46.fc38.x86_64kdump.img: ASCII cpio archive (SVR4 with no
> [root@ci-vm-10-0-139-47 ~]# file /boot/initramfs-6.0.9-200.fc36.x86_64kdump.img
>/boot/initramfs-6.0.9-200.fc36.x86_64kdump.img: ASCII cpio archive (SVR4 with no CRC)
>This is fc1c79ff ("Seperate dracut and dracut-squash compressor for
>zstd") disabls passing "--compress zstd" to dracut when the squashfs
>dracut module is going to be used. Is the change intentional? If not,
>maybe we should drop this patch and do it in mkdumprd instead.
>Btw, it seems "--compress zstd" or "--zstd" no longer compresses
>initramfs in rawhide (2022-11-24) whereas in f36 it works as expected. Another
>difference between rawhide and f36 is in 36 with "--zstd" not specified,
>dracut will gzip-compress the initramfs while in rawhide, it doesn't
>compress the initramfs.
After having a further look, I realize the latter issue has nothing to
do with the difference between rawhide and f36. Once the dracut squash
module is enabled, "--compress zstd" will no longer work.
After having discussion with Tao, I realize my confusion is due to
to my misconception. In fact, dracut explicitly prevents compressing
the initramfs when the squash module is used because there is very
little benefit when compressing it for a second time so it's pointless
to pass "--compress zstd" to dracut in this case. Thanks to Tao's