Re: ext4 warnings: extent tree (at level 2) could be narrower.

[Darrick J. Wong]

On Sat, Dec 14, 2019 at 12:02:26AM +0100, Pavel Machek wrote:
> Hi!
> 
> Periodic fsck kicked in on x86-32 machine. I did partial update in the
> meantime, and was running various kernels including -next... Now I'm
> getting:
> 
> data: Inode 1840310 extent tree (at level 2) could be narrower. IGNORED.
> 
> on 5 inodes.  Is it harmless, or does it mean I was running buggy
> kernel in the past, or...?

That message means that e2fsck has found that the extent tree could be
smaller than it actually is; the lack of any other complaints about the
extent tree mean that it's ok.

The kernel cannot shrink the extent tree on its own (but e2fsck can), so
this message is where e2fsck would have applied that optimization.

IOWs: mostly harmless, but the kernel was (and still is) a bit deficient.

--D

> Best regards,
> 									Pavel
> 
> -- 
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html