[Users] New setup - deploy OpenVZ or wait for VZ7?

[Konstantin Khorenko]

On 06/06/2016 07:13 PM, Сергей Мамонов wrote:
>  > Yes, i know it's still possible to create an image which will be compacted not that efficiently, but this becomes quite a rare case.
>
> But in irl  - get random prodaction node and first container with max delta (data vs image size) -
> ploop-balloon  discard /vz/private/93713/root.hdd/DiskDescriptor.xml --stat
> Balloon size:        0MB
> Data size:       30845MB
> Ploop size:      51200MB
> Image size:      47546MB
>
> ploop-balloon  discard /vz/private/93713/root.hdd/DiskDescriptor.xml --defrag
> ...
>
> ploop-balloon  discard /vz/private/93713/root.hdd/DiskDescriptor.xml --stat
> Balloon size:        0MB
> Data size:       30845MB
> Ploop size:      51200MB
> Image size:      47433MB

Sergey, good! You are welcome to upload the image data:
<link sent privately>

We've already done one more step further, interesting to know if it will be big or small one in your case.

Anyone else?

> And already have 17Gb wasted space for 30Gb data after compact with defrag.
> ( on node openvz 6  - 2.6.32-042stab114.5 kernel, ploop-1.15-1.x86_64 and e4defrag2 builded from https://github.com/dmonakhov/e2fsprogs/tree/e4defrag2 with commits from 16 May).
>
> In irl we have significan overhead on disk operations on compact ploop images.
>
> In irl we regular have ploop images which we cannot umount - https://bugs.openvz.org/browse/OVZ-6689 !!!
>
> And from time to time backup and compact failed with strange situations like - https://bugs.openvz.org/browse/OVZ-6547

And this is a good illustration why Virtuozzo 7 is so different from OpenVZ 6.
Getting free and commercial tools code more and more different lead to issues we don't face in commercial product.
i believe OpenVZ users will really benefit in stability from Virtuozzo 7, where the code is exactly same both in commercial and free versions.

--
Konstantin

> 2016-06-06 18:13 GMT+03:00 Konstantin Khorenko <khorenko at virtuozzo.com <mailto:khorenko at virtuozzo.com>>:
>
>     On 06/06/2016 02:23 PM, Volker Janzen wrote:
>
>         Hi Sergey,
>
>             On 14:39 Sun 05 Jun , Volker Janzen wrote:
>
>
>                     Unfortunately no. We don't support upgrade from pre-release version to the final one.
>
>
>                 When I use a CentOS 7 as base system and install VZ7 afterward it's not possible to upgrade, too?
>
>
>             There is only one supported configuration for new installations -
>             clean Virtuozzo 7 installation.
>
>
>         okay I see. My setup will be unsupported if installed on plain CentOS 7 either way.
>
>
>                         It also seems to lack some documentation for my use cases, but I need to start
>                         with VZ7 sooner or later.
>
>
>                     What usecases are you talking about?
>
>
>                 My current OpenVZ setup has LVM involved.
>                 I want to be able to use simfs based storage on an underlaying LVM volume.
>
>
>             Why do you prefer simfs instead of ploop? Did you see comparison simfs vs ploop?
>             https://openvz.org/CT_storage_backends
>
>
>         I think you asked me about this some time ago. The matrix states: Reliability
>         Low: big amount of files produce ext4 corruption so often
>
>         Why should I use something that tells me it's not reliable?
>
>
>     Even according to
>     https://github.com/pavel-odintsov/OpenVZ_ZFS/blob/master/openvz_storage_backends.md
>     (which seems to be used as a source of recent page update) this row is incorrect, this info has just been added by Narcis Garcia and is to be corrected.
>
>     i don't want to start a holly war here, i won't tell that ZFS is worse or whatever,
>     i just know that we really do power crash testing and know the results.
>     And i'm certain that our default suggested solution is good and stable.
>
>     Yes, there are drawbacks - the most important one now is usage overhead (sic!, not stability for a long time already), and we improve it.
>     And gained quite a good progress. Just did a ploop compaction of my personal work Container, created 03.07.2014 (lot of gits, makes, etc.):
>
>     # ploop-balloon discard /vz/private/105/root.hdd/DiskDescriptor.xml --defrag
>     ...
>     # ploop-balloon discard /vz/private/105/root.hdd/DiskDescriptor.xml --stat
>     Balloon size:        0MB
>     Data size:       29189MB
>     Ploop size:     102400MB
>     Image size:      29057MB
>
>     Yes, i know it's still possible to create an image which will be compacted not that efficiently, but this becomes quite a rare case.
>     Do you have such an image? Send it to us.
>
>     Thank you.
>
>     P.S. in fact we don't need full image in most cases, only metadata is essential, so if you worry about data and confidentiality, no problem here:
>     # e2image -r /dev/ploopXXp1 - | bzip2 > image.e2i.bz2
>
>     --
>     Best regards,
>
>     Konstantin Khorenko,
>     Virtuozzo Linux Kernel Team
>
>
>         The /vz partition has also the big advantage of using LVM snapshots and it allows rsync of the container data to another host with less overhead.
>
>         Also the need to compress the ploop files does not seem to be something I'm willing to do.
>
>
>         Regards
>              Volker
>
>
>                 And I want to be able to setup KVM based VMs that have a LVM based disk, too.
>                 In best case KVM VMs can be created from a template, as with the container VMs.
>
>
>             Den, is it possible in Vz7?
>
>                 Regards
>                     Volker