Btrfs fast clone

[Robvil]

Hi,

I am currently using a Synology DS1815+ for my primary repository. The big issues with this is the extreme slow synthetic backup via SMB share. 48 hours for 5TB.
I read on Synology.com, DSM 6.1 will have support for btrfs fast clone via SMB connections.

Question: Will this provide the same funtionality as Win2016 Refs 3.1 regarding only making a pointer to identical data?

Robert

[Andreas Neufert]

Hi Robert,
I think the software (Veeam) need to actively support this. And it is not planned in the short term.

30MB/s speed (2x for read write) isn´t that good. Is it a 1GbE network?

Maybe you can add the Synology as iSCSI volume to the Veeam Server and format it with ReFS 3.1 (when used with Windows 2016) to use the new block cloning.

Please describe as well how the setup is done.
Were is the B&R Server located? What Mount Server is selected for the repository? Which is the Gateway Server for the Repository?
Network connections and speed?

Backup Mode and Settings (SF+I ? Compression? InlineDedup? Per VM chain or per Job chain?...)

[Robvil]

I think the software (Veeam) need to actively support this. And it is not planned in the short term.
A: ok

30MB/s speed (2x for read write) isn´t that good. Is it a 1GbE network?
A: 2x1Gbit/s bond til Cisco

Maybe you can add the Synology as iSCSI volume to the Veeam Server and format it with ReFS 3.1 (when used with Windows 2016) to use the new block cloning.
A: A good idea. Maybe i´ll try this at a point

Please describe as well how the setup is done.
Were is the B&R Server located?
A: Same subnet/Lan as the repository with bonded 1Gbit/s nics

What Mount Server is selected for the repository?
A: Not sure what you mean? From the Veeam server, repository is configured as a SMB share

Which is the Gateway Server for the Repository?
A: Veeam server

Network connections and speed?
A: Bondet multiply 1Gbit/s nic´s where Synology is configured with SMB version 3

Backup Mode and Settings (SF+I ? Compression? InlineDedup? Per VM chain or per Job chain?...)
A: Forever incremental with compression and inline de-dupe. Per Job chain.

[Andreas Neufert]

You can try if per VM chain will speed up the Merge and Backup process as more streams are started to the target storage

[Robvil]

You can try if per VM chain will speed up the Merge and Backup process as more streams are started to the target storage
A: I think i´m confused. Can you explain the difference in Veeam how-to?

Just testet with a iSCSI connected drive with IOMeter to the synology and with 256Kbit access test (tried different read/write modes) - here I get from 50MBps to 85MBps.
Testing with 4Kbit access I get 8MBps to 10MBps ....

Volume is formattet with 64kb block size (both synology and OS).

[Andreas Neufert]

OK I assume that you had tested with a single stream (IO Meter).

The Standard Veeam Setting is a "Per Job" chain. That means you backup 20VMs with it´s 40 VM disks to a single backup file per restore point. So a single write stream is used.
If you enable "Per VM chain" at the Repository settings, for each VM a own backup chain is created at target storage. How many in parallel depends on the Proxy and Repository task count setting. So at least you will see 2-4 write Streams per Job.
That way you teaming will be better used as well.

If you then use Win2016 with ReFS 3.1 formated block volume (iSCSI) and it´s "Fast-Merge" processes, this would be the optimum for your storage.

[Robvil]

I´m confused. I have added 2 ekstra 4TB drives to my raid5 for more IO, so i now have a total of 6 disks in raid level.
Last night the full incremental took 2 hours and 9 minuttes to complete vs. 48 hours on my 4 disks raid5.

Is there a raid penalty in linux raid with 4 disks in raid5 vs. more disks...

[Andreas Neufert]

2 more discs will increase speed, it depends really on the raod controller and storage. Maybe adding 2 discs repaired something in the storage.

[Robvil]

ds1815+ is software raid. There was no raid/volumes errors acording to the synology box.

[Andreas Neufert]

I had that before. Slow performance with connection drops. Synology Support has a tool that you can run on the storage that checks for data corruption or some internal logic stuff. In the customer case the raid needed to be initialized from scratch (with copy of data elsewhere) and after that it performed really good and stable.

[pesos]

We back up to a Dell MD3200 with twelve 2tb nearline sas drives in raid6, refs 64k. Backup performance is totally fine, but "fast clone" performance is anything but fast.

We have synthetic full set to run on Fridays, so it has 5 backups to inject into the synthetic full and change into rollbacks. The transformation takes 7.5 hours! Shouldn't this be significantly faster?

I've noticed that b&r will run up to 3 transformations at once, even though the repository is set to only allow one action at a time.

[musclewarrior]

The latest verion of DSM on the Synology NAS supports 'fast clone' when using the BTRFS file system on the NAS along with SMB.

I've tested this using Windows and a SMB Share on the NAS and it works as expected.

When I setup some Veeam backup jobs to the NAS over SMB, I noticed it didn't use the 'fast clone' function.

This could be a major draw card to cheaper NAS's if you could implement this feature without having to resort to setting it up as a iSCSI repository (For Fast Clone). It would also allow greater protection from Ransomware for the Backup files.

Could it be an easy feature to add, or is it a bit more complex than that?

Thanks.

[PTide]

Could it be an easy feature to add, or is it a bit more complex than that?

Based on our development experience with adding BTRFS support in different products, I would say that you can never know for sure until you start developing a feature that involves some sort of interaction with BTRFS. The filesystem is a really complicated piece of technology that tends to change and evolve on the fly. As Andreas has mentioned, should we decide to implement that, it won't be a short-term thing.

Thanks!

[GT-Engineer]

P.Tide

Any update on adding "Fast Clone" for BTRFS support?

[PTide]

Hi,

No, no news as of yet.

Thanks!

[Gerald]

While I would guess the speed problem discussed here is probably mostly related to
veeam-agent-for-windows-f33/solved-veea ... 63558.html
and doesn't really need fast clone to resolve it...

...I would like to add that BTRFS fast clone support for Linux/NAS shares would be really great. I have no idea though if Samba currently implements the necessary APIs to do such a thing from the client side?