2 replies Latest Post - ‏2013-07-25T21:30:03Z by CHofmeister
178 Posts

Pinned topic XIV and Space Reclamation

‏2013-07-23T16:17:51Z |
hi guys
I have XIV Issues related with space used either Thin and Thick Pools.
First Thin Pool that is more critical since I don't want it to be in read only.
This is Suse Linux Virtual Server running on Vmware. XIV Volume configuration:

as you can see Soft Size is: 11424GB but XIV indicates 6910GB as used by Volumes but I don't know the reason why is shows 95% as critical.

Checking the volumes in the Linux and Vmware volumes are not even 50 % used.

How can I reflect real size in XIV so I won't have problems having this volumes in Read Only Mode?


Same scenario is happening with Vmware Thick Volume which is alerted in XIV as 90% used when in Vmware is only 45% used.

any idea who to fix this would be great

thanks a lot guys

Updated on 2013-07-23T16:18:43Z at 2013-07-23T16:18:43Z by kopper
  • kopper
    178 Posts

    Re: XIV and Space Reclamation

    ‏2013-07-24T18:43:07Z  in response to kopper

    any one guys?



  • CHofmeister
    10 Posts

    Re: XIV and Space Reclamation

    ‏2013-07-25T21:30:03Z  in response to kopper


      It sounds like you have a couple things working against you.  First off the XIVs do there thing, in 17GB chunks. So everything is rounded to that number.  For example if you have a drive with 1GB of data, it will take up 17GB on the XIV.  Like wise a 20GB volume will use up 34GB on the backend.  This rounding will result in the totals being higher.  At my company we migrated an old lunix box to the XIV that had 100+ 4GB LUNs.  This resulted in a "Huge" waste of space on the backend.

      As for the individual drive usage, the XIV is a block level storage, so it only looks at what blocks have ones and zeroes.  When deleting a file at the OS level, it does not actually delete the data, it simply deletes the File Allocation Table entry.   So if you copied 100GB of data to an empty volume, then deleted that data, the OS would display it as being empty.  However the XIV still sees all of those ones and zeroes, and registers that space as being used.  There are tools that can write zeroes to all of the empty space.  If you run these the XIV will slowly reclaim the space, as it does its disk scrubbing in the background.  The disk scrubbing runs all the time in the background.  I have not seen anything official but have heard its roughly 30 days to reclaim all the space (depending on how busy the box is.