4 100G zvols + 1 20G dataset = 100G used space !?!?!

[Stephen J]

Just curious here. In my vmtank volume I have 4 zvols of 100G each and 1 20Gig dataset with 10.7G used. 3 of the zvols have roughly 45Gigs of thick provisioned VM Disks on them. Why is /mnt/vmtank showing 100G used?

Stephen

 

[paleoN]

Stephen, it may just be me, but I have no idea what your setup is. Perhaps the output of these commands will help me:

Code:

zpool status -v
zfs list
df -h

 

[Stephen J]

Code:

zpool status -v
config:

        NAME        STATE     READ WRITE CKSUM
        vmtank      ONLINE       0     0     0
            mirror    ONLINE       0     0     0
             da5p2   ONLINE       0     0     0
             da13p2  ONLINE       0     0     0
            mirror    ONLINE       0     0     0
             da6p2   ONLINE       0     0     0
             da14p2  ONLINE       0     0     0
zfs list
NAME                             USED  AVAIL  REFER  MOUNTPOINT
vmtank                            420G  3.16T   100G  /mnt/vmtank
vmtank/vmresources                 20G  9.27G  10.7G  /mnt/vmtank/vmresources
vmtank/vmtarget1                  100G  3.22T  35.9G  -
vmtank/vmtarget2                  100G  3.25T  9.21G  -
vmtank/vmtarget3                  100G  3.25T  7.63G  -

df -h
Filesystem                      Size    Used   Avail Capacity  Mounted on
vmtank                       3.3T    100G    3.2T     3%    /mnt/vmtank
vmtank/vmresources            20G     11G    9.3G    54%    /mnt/vmtank/vmresources

 

[Stephen J]

This is what the browser interface shows. Maybe it is a bug.

Code:

Volume 	Path 	                                                 Used 	Available 	Size 	Status 	Available actions
morodata 	/dev/zvol/morodata/zimbradatastore 	   - 	              - 	750G   - 	
vmtank 	/dev/zvol/vmtank/vmtarget2 	                   - 	              - 	100G   - 	
vmtank 	/dev/zvol/vmtank/vmtarget3 	                   - 	              - 	100G   -	
vmtank 	/dev/zvol/vmtank/vmtarget1 	                   - 	              - 	100G 	  - 	
vmtank 	/mnt/vmtank 	                          100.0 GiB (2%) 	3.2 TiB 	3.3T   HEALTHY 	
vmtank 	/mnt/vmtank/vmresources 	          10.7 GiB (53%) 	9.3 GiB 	20.0G HEALTHY 	

Stephen

 

[paleoN]

Maybe it is a bug.

Could be. What version are you running anyway? Are you using any snapshots? Looks like this is what you should run

Code:

zfs list -r -t all

Did you reserve space for the vmtarget data sets when you created them?

 

[Stephen J]

vmtargets are not datasets they are zvols so there is no reserved space setting. I did not create a specific data set for each zvol. They are all created directly on the vmtank volume. Should I have created datasets for them? I guess that would make a lot of sense since it would allow me to snapshot and replicate them individually.

I am running 8.0.4-RELEASE-x64

Stephen

 

[paleoN]

Code:

zfs list
NAME                             USED  AVAIL  REFER  MOUNTPOINT
vmtank                            420G  3.16T   100G  /mnt/vmtank
vmtank/vmresources                 20G  9.27G  10.7G  /mnt/vmtank/vmresources
vmtank/vmtarget1                  100G  3.22T  35.9G  -
vmtank/vmtarget2                  100G  3.25T  9.21G  -
vmtank/vmtarget3                  100G  3.25T  7.63G  -

The 320G of the 420G under USED is from the 3 zvols and the one file extent. Which just leaves the 100G under the REFER that's using the extra 100G. Try running

Code:

du -h /mnt/vmtank

Did you ever benchmark your striped mirrors? You may have left the 100G test file laying around somewhere.