[linux-lvm] lvcreate hangs forever during snapshot creation when suspending volume

[Zdenek Kabelac]

Dne 02. 08. 22 v 5:01 Thomas Deutschmann napsal(a):
> Hi,
> 
> Zdenek Kabelac wrote:
>> Now - you suggests you are able to reproduce this issue also on your bare
>> metal hw - in this case run these 3 commands  before  'lvcreate'
> 
>> Zdenek Kabelac wrote:
>> Note: you could always 'experiment' without lvm2 in the picture -
>> you can ran   'fsfreeze --freeze|--unfreeze'  yourself - to see whether
> even
>> this command is able to finish  ?
> 
> fsfreeze caused the same problem :/
> 
> I also changed filesystem from xfs to ext4 just in case... same issue.
> 
> For testing I stopped the MDRAID and removed one NVMe disk which I
> cleared and where I created a new ext4 partition. Running
> 
>    $ fsfreeze --freeze /mnt/test
> 
> returned within seconds and I was unable do any I/O against /mnt/test
> as expected.
> 
> I unfreezed the filesystem and started to copy ~50GB to the volume.
> After waiting 5 minutes and verifying that /proc/meminfo didn't list
> any 'dirty' pages, I re-run the fsfreeze command which caused the
> same issue -- system hangs. :/
> 
> I will repeat the test with the other NVMe later...
> 
> So probably a kernel/driver issue or hardware problem.
> 

Hi

So as guessed earlier - unrelated to lvm2.

You likely need to discover what is wrong with your 'raid' device ?
Was your raid array fully synchronized ?

Do you have only problem with one particular  MD 'raid' on your system - or 
any other 'raid' you attach/create will suffer the same problem ?

Is it 'nvme' related on your system ?

Are the 'individual' nvme  devices running fine - just when they are mixed 
together into a single array you get these  'fsfreeze' troubles ?

Regards

Zdenek