What is difference between total used and total physical used for a volume

[jsachdev_tm]

Hi,

I would like to know that what is difference between total used and total physical used as shown in below output

an0990-na-cl1::> volume show-space test_vol_iscsi

      Vserver : test_svm_iscsi
      Volume  : test_vol_iscsi

      Feature                                    Used      Used%
      --------------------------------     ----------     ------
      User Data                                5.02GB        50%
      Filesystem Metadata                       212KB         0%
      Inodes                                     16KB         0%

      Total Used                               5.02GB        50%

      Total Physical Used                       268KB         0%

For my every volume there is huge difference between the two, the above volume "test_vol_iscsi" has gurantee none.

an0990-na-cl1::> vol show-space testroskilde

      Vserver : an0990-na-cl1-fcp
      Volume  : testroskilde

      Feature                                    Used      Used%
      --------------------------------     ----------     ------
      User Data                               152.6GB        28%
      Filesystem Metadata                     64.85MB         0%
      Inodes                                     32KB         0%
      Snapshot Reserve                        27.50GB         5%

      Total Used                              180.2GB        33%

      Total Physical Used                     75.43GB        14%

The above volume testroskilde has space gurantee "volume"

Regards..

JP

[ekashpureff]

JP -

'Total Used' is the amount of data that should be seen from the client side.

''Physical Used' is the amount of physical storage used on the NetApp.

In your first example for 'test_vol_iscsi' it looks like there hasn't been any data written to the LUN in the volume.

The client sees a 5.02GB LUN, but on the filer it isn't taking up any space yet.

In the second example it looks like you have dedupe and/or compression turned on.

The client(s) have written 152GB of data  and there's a snapshot reserve of 27.5GB, but the footprint on disk is only 75.43GB.

You may also wish to look at the 'aggr show-space command to see the effect of volume space guarantee ...

I hope this response has been helpful to you.

At your service,

Eugene E. Kashpureff, Sr.
Independent NetApp Consultant http://www.linkedin.com/in/eugenekashpureff
Senior NetApp Instructor, FastLane US http://www.fastlaneus.com/
(P.S. I appreciate 'kudos' on any helpful posts.)

[jsachdev_tm]

I have just recently created this volume "test_vol_iscsi" for testing purpose, then why it is showing 5.02 GB used space ?

Vserver   Volume       Aggregate    State      Type       Size  Available Used%
--------- ------------ ------------ ---------- ---- ---------- ---------- -----
test_svm_iscsi
          test_vol_iscsi
                       n02_sas_1200 online     RW         10GB     4.98GB   50%

an0990-na-cl1::> volume show-space  test_vol_iscsi

      Vserver : test_svm_iscsi
      Volume  : test_vol_iscsi

      Feature                                    Used      Used%
      --------------------------------     ----------     ------
      User Data                                5.02GB        50%
      Filesystem Metadata                       212KB         0%
      Inodes                                     16KB         0%

      Total Used                               5.02GB        50%

      Total Physical Used                       268KB         0%


an0990-na-cl1::> volume show-footprint test_vol_iscsi

      Vserver : test_svm_iscsi
      Volume  : test_vol_iscsi

      Feature                                   Used    Used%
      --------------------------------    ----------    -----
      Volume Data Footprint                    268KB       0%
      Volume Guarantee                            0B       0%
      Flexible Volume Metadata               523.2MB       0%
      Delayed Frees                           6.82MB       0%

      Total Footprint                        530.3MB       0%

there are no luns present in this volume, even it is not used for anything like snapmirror etc.

Also when can I say this volume is full when it total used reaches 10GB or when total physical used reaches 10GB ?

Volume total size is 10GB.