this post was submitted on 11 Jan 2025
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Initramfs and initrd are 2 different things, the problem where the confusion happens is that initrd is deprecated since a few years.
Now, systemd has implemented an interface called systemd-initrd which basically is initramfs.
I guess here is were the confusion lies. Nowadays everything is initramfs even if it called initrd.
The original initrd differs from initramfs, but it is no longer a thing.
Sorry if i came across a little bit snappy have not had a great week so far.
Everything is fine. It's always nice to learn something new. Hope you will have better week!
Edit: You are right. I looked it up:
There seems to be an actual technical difference, in the kernel, between an initrd and an initramfs. An initrd is apparently mounted like a normal file system, it's just in RAM instead of a backed by a block device. An initramfs is a tmpfs into which a (usually cpio) archive is extracted into. The initramfs apparently would be preferable generally, because the kernel understands that it's a ramdisk, whereas with an initrd it would go through the block device layer, which would mean it would use more ram: If you read a file from an initrd, the kernel would copy the file to ram (unnecessarily, since it's already in ram) like it would for a filesystem on disk, but for a tmpfs/initramfs, it understands it doesn't need to do that.
From a user's perspective there is no significant functional difference I don't think, and I don't think this relevant to OP's question, that probably has more to do with the userspace tools.
https://en.m.wikipedia.org/wiki/Initial_ramdisk
As i said 2 different things, initrd was used to create a ramdisk, a block device. Initramfs basically directly offers a filesystem instead of a block device.
systemd has now a interface called systemd-initrd: https://github.com/systemd/systemd/blob/main/docs/INITRD_INTERFACE.md
initrd was deprecated see here: https://lkml.org/lkml/2020/7/14/1508
Yes, sorry, you are correct. I've edited my other comments.