cad wrote: ↑06 Jan 2021, 03:08
roadie wrote: ↑05 Jan 2021, 22:03
The same happens with anything not presently in the kernel such as zstd compressed modules. Which leads to a question.....
Has anyone compressed the modules with zstd and had success with booting the kernel? I've done 2 attempts so far, and the kernel patches cleanly and boots, but the kernel modules are not being loaded. They're present in /lib/modules, but nothing is modprobed during the boot. I've tried both standard Porteus initrd, and
neko's initrd.zstd, but no joy.
roadie,
My guess is that your described attempts were with kernels antecedent to 5.9? (If using Porteus, it is almost certain they were.)
To my knowledge, ZSTD was much improved and merged upstream (mainlined) since kernel 5.9 (native ability to deal with ZSTD-compressed kernels, initrds and kernel modules). Try it in kernel 5.10.x and I would think you will find it to be pretty much flawless.
I wish it were that easy with AUFS at this time. Perhaps, it will not be very long before it, too, gets mainlined so that we won't have to go through what we are right now.
cad,
Yes, I'm using 5.10.2 and zstd support is there for the kernel itself and init, but it's not there if you want to compress the kernel modules with it. The default is gzip and xz is available. With a standard kernel, if the modules are not being compressed, the config will show this: CONFIG_MODULE_COMPRESS is not set. If you do choose to compress the modules. you have this for an unpatched kernel:
Code: Select all
CONFIG_MODULE_COMPRESS=y
CONFIG_MODULE_COMPRESS_GZIP=y
# CONFIG_MODULE_COMPRESS_XZ is not set
With a patched kernel, this:
Code: Select all
CONFIG_MODULE_COMPRESS=y
# CONFIG_MODULE_COMPRESS_GZIP is not set
# CONFIG_MODULE_COMPRESS_XZ is not set
CONFIG_MODULE_COMPRESS_ZSTD=y
I was hoping that compressing the modules might speed up the boot process, I can't say right now that compressing them even with gzip makes a huge difference and I haven't tried xz. That will be the next one, at the least maybe I'll find out it's all for not much gain.
I know what you mean regarding aufs, I find overlay is very close to aufs in usefulness,
neko found a way around the module activation problem, and it's sure a lot easier to compile since there's no patching. Myself, I don't think aufs will ever be put into the mainline kernel.