[Users] Deleting a snapshot of eight disks took more than fifteen minutes

[Simon Grinberg]

----- Original Message -----
> From: "Shu Ming" <shuming at linux.vnet.ibm.com>
> To: "Simon Grinberg" <simon at redhat.com>
> Cc: "users at oVirt.org" <users at ovirt.org>
> Sent: Tuesday, July 3, 2012 12:37:31 PM
> Subject: Re: [Users] Deleting a snapshot of eight disks took more than fifteen minutes
> 
> On 2012-7-3 17:01, Simon Grinberg wrote:
> > It depends.
> >
> > Block device or NFS?
> 
> NFS
> 
> > Did you had data on the deleted snapshot?
> Got some. Not too much
> 
> > Did you had wipe after delete marked or not?
> No.
> 
> > Did the snapshots contain data?
> Got some. Not too much
> 
> > Did you delete a snapshot or did you revert to a snapshot?
> Just deleting a snapshot.

Considering that:
1. You had data on the snapshots
2. You've deleted snapshots 
3. You have 8 disks

Then is sounds reasonable.

Deleting a snapshot is merging two files into one. For the sake of roll back it is done by actually copying the first, writing the changes of the second on top and then inserting this new file into the snapshots chain.  This is time consuming depending on your storage performance and the amount of data in the snapshots. And you do it 8 times, one per disk.

    

> 
> 
> >
> >
> >
> >
> > ----- Original Message -----
> >> From: "Shu Ming" <shuming at linux.vnet.ibm.com>
> >> To: "users at oVirt.org" <users at ovirt.org>
> >> Sent: Tuesday, July 3, 2012 11:48:35 AM
> >> Subject: [Users] Deleting a snapshot of eight disks took more than
> >> fifteen	minutes
> >>
> >> Is it reasonable?   I created snapshot1 and snapshot2 for the
> >> eight
> >> disks and then tried to delete snapshot2.   And it took 15+
> >> minutes
> >> to
> >> finish the operation.
> >>
> >> Here is the disk list:
> >>
> >> my-vm1_Disk1          40 GB                           3 GB
> >>                                  data                   Thin
> >> Provision     VirtIO                  OK          2012-Jun-27,
> >> 13:24:01
> >> my-vm1_Disk2         10 GB                            10 GB
> >>                                data                   Preallocated
> >>        VirtIO                  OK          2012-Jun-25, 23:19:00
> >> my-vm1_Disk3          4 GB                              < 1 GB
> >>                              data                   Thin Provision
> >>      VirtIO                  OK          2012-Jun-26, 23:27:40
> >> my-vm1_Disk4          3 GB                              3 GB
> >>                                 data                   Thin
> >>                                 Provision
> >>      VirtIO                  OK          2012-Jun-27, 13:24:01
> >> my-vm1_Disk5          3 GB                              3 GB
> >>                                 data                  Thin
> >>                                 Provision
> >>      VirtIO                   OK           2012-Jun-27, 13:24:01
> >> my-vm1_Disk6          4 GB                              4 GB
> >>                                 data                  Thin
> >>                                 Provision
> >>      VirtIO                   OK           2012-Jun-27, 13:24:02
> >> my-vm1_Disk7          5 GB                              5 GB
> >>                                 data                  Thin
> >>                                 Provision
> >>      VirtIO                   OK          2012-Jun-27, 13:24:02
> >> my-vm1_Disk8          6 GB                              6 GB
> >>                                 data                  Thin
> >>                                 Provision
> >>      VirtIO                   OK          2012-Jun-27, 13:24:02
> >>
> >>
> >>
> >> --
> >> Shu Ming <shuming at linux.vnet.ibm.com>
> >> IBM China Systems and Technology Laboratory
> >>
> >>
> >> _______________________________________________
> >> Users mailing list
> >> Users at ovirt.org
> >> http://lists.ovirt.org/mailman/listinfo/users
> >>
> 
> 
> --
> Shu Ming <shuming at linux.vnet.ibm.com>
> IBM China Systems and Technology Laboratory
> 
> 
>