[ SOLVED ] "Sparse file not allowed" message on boot of LL4 installed to BTRFS

[kpanic]

And doing so JonMikelV, you help the developers.

Everybody hopes (well, some of us ) that the project won't fail.
We all (well some of us ) have seen what happened to ReiserFs for example,
a project which came out with at least equal hype

[JonMikelV]

trinidad - Thanks for the link showing this is a general Grub + BTRFS issue and not specifically Lite related.  I think that pretty much "solves" this for me.  :-)

kpanic - Thanks for the details you provided about BTRFS.  I have used it elsewhere (in a non-production capacity) and haven't had any issues which is why I was surprised to run into it here (though this is the first time I've used it on a boot drive).
I don't disagree that it's a work in progress, but I figure I'm working with non-critical stuff so I might as well play with it and see if I can help progress that work forward.  ;-)

[trinidad]

https://askubuntu.com/questions/100329/message-sparse-file-not-allowed-after-installing-on-a-btrfs-filesystem

Been that way for quite a while.

TC

[kpanic]

As you see, you already installed LL on ext4 and it worked fine, right?
And when you install it on Btrfs, it won't work - that is my definition of a "pile of crap".

But it is not just that. I have read many articles about file systems and I know the subject quite well.
For example people (experts) have made stress tests and compared results between various files systems.
When it comes to reliability (read/write errors etc), guess which one got the worst results.

I am not trying to say that Btrfs is a bad file system but I think it is - in it's current state - still a work in progress,
while ext4 is very stable and reliable fs. If you like to use Btrfs, by all means do so..

[JonMikelV]

Thanks for your quick reply, kpanic.

The disclaimer ("renunciation of one's right or claim") was meant to let people know this is not an issue that needs to be addressed in a timely manor.  In other words it's not an "I need this fixed now or I'll lose my job and it's all your fault" type of post.  Sorry if my usage confused you.

An actual pile of crap is "a pile of crap" by definition, however BTRFS (by definition) is not - can you expand on why you think it is one?

As for installing on ext4, as stated I have already done that in one VM.  Now I'm trying BTRFS in another - in this particular case it's so I can play around with Timeshift using snapshots that are natively supported by BTRFS rather than needing an additional partition which ext4 drives appear to need for snapshots.

This is research, all done in VMs, to help educate me on how I want to proceed with various features when I move to a physical hardware install with real-world usage.

[kpanic]

First of all, what did you mean with that "disclaimer"? Do you know what the word means?

I have an idea what the problem may be. Btrfs is a pile of crap - install your Linux on ext4.

[JonMikelV]

Disclaimer - I'm playing around with VMs (using KVM on unRAID, if anybody cares) so there's nothing at stake here - I can wipe & reinstall without any issue.
I did a standard install of LL4 (to ext4) with no issues.  I then did a non-standard install to a BTRFS partition because I wanted to play around with Timeshift.
While the ext4 based install boots just fine, I find that the BTRFS install starts with the following message:

error: sparse file not allowed.
Press any key to continue...

Whether I press a key or let the message go away on it's own (takes about 20 seconds) the OS loads apparently without issue but seems to take a LOT longer to load than the standard ext4 installation (ext4 @ ~38 seconds vs. BTRFS @ ~6.5 min).

Does anybody have any thoughts on what the "Sparse file not allowed" message is about and whether it and/or the BTRFS OS is the cause for the LONG boot time?
Thanks!