First backup / daily snapshot slow

[ntblade]

Hi all,
I've setup a simple test of pbs. The hardware is modest but there is only one vm koozali SME server to backup. The promox pve host has 6GB RAM and 4 is given to the vm. I did an initial full backup with the machine powered off which took several hours. I've scheduled a daily snapshot @ 2am which I thought would have been much quicker. However this is also taking several hours to complete. I would have thought the snapshot backup would be very quick. Am I doing something wrong?

Thanks

 

[fabian]

if the VM is powered down at or between backups, the client will have to read and hash all the data to decide what to upload. if you want really fast incremental backups, you need to keep the VM running..

 

[ntblade]

if the VM is powered down at or between backups, the client will have to read and hash all the data to decide what to upload. if you want really fast incremental backups, you need to keep the VM running..

Thanks for the swift reply Fabian. I'll let it run overnight and report back

N

 

[tafkaz]

if the VM is powered down at or between backups, the client will have to read and hash all the data to decide what to upload. if you want really fast incremental backups, you need to keep the VM running..

Hi Fabian,
just learned this myself. Backups of non running VMs are very slow compared to the incredible speed with backups of running VMs.
So i was wondering if there would be any solution, technically speaking, to this, what do you think?
Else i would just backup poolwise in the future, and file the non running VMS into a "Backup only once a week" pool.
However, there would be the danger of forgetting to change the pool, if the VM was started, as this would have to be done manually...
any ideas?
thanks
Sascha

 

[fabian]

at some point there might be some way to persist the bitmap that tracks 'dirty' content, but for the time being, not backing those VMs up (or not backing them up as often) seems like a valid workaround. presumably their content does not change much while they are not running

 

[tafkaz]

Hi Fabian,

thanks a lot for your reply. Yes, i guess the workaround will perfectly do for us for now.

However, as dirty bitmaps will be lost also in quite a few other scenarios (HA Migations for example), we would really appreciate some improvements on this field.

Which of course does not at all mean, that we don't like PBS in the already released state.
In fact we use it on quite some systems now, and couldn't be any happier with the product.
It is simply great an very well done!

Thanks for your outstanding work!!!


cheers
Sascha