MSA2060, Veeam and reFS - wasted space ?

[IMPI-Ced]

Hi,

we are using a MSA2060 directly attached using SAS to a Proliant under wiindows 2022, full with SSD and reFS formatted.

I have less an less sapce on it and can not explained it.

Reading on forums, i saw things about trim/space reclaiming..

All seems well configured as i have :

PS C:\Windows\System32> .\fsutil.exe behavior query disableDeleteNotify
NTFS DisableDeleteNotify = 0 (Autorise l’envoi d'opérations TRIM au dispositif de stockage)
ReFS DisableDeleteNotify = 0 (Autorise l’envoi d'opérations TRIM au dispositif de stockage)

I read about using " Optimize-Volume e -ReTrim -Verbose" not better

Also about using "sdelete -z e:" but then it seems it "eats" space (that i recover using "optimize-volume" again)

How can i verify that space isn't wasted ?

Thanks for your help

Ced

[IMPI-Ced]

Hi,

i'm still reading to see where could be the issue, and maybe another clue : on veeam forum they say defrga should not be done on reFS volume as it could "break" the cloning advantage. It is a full SSD MSA then i never did any defrag... but... it was scheduled by default by Windows and then runing each week !

I disabled it and i hope it will then be better for next backup.

Does anyone know if the issue could be there ?

Thanks

[ArunKKR]

Hi,

As per microsoft advisory, for SANs, if features such as thin provisioning, TRIM/UNMAP, or Offloaded Data Transfer (ODX) are required, NTFS must be used. 

https://learn.microsoft.com/en-us/windows-server/storage/refs/refs-overview

NOTE: The above-mentioned URL will take you to a non-HPE Web site. HPe does not control and is not responsible for information outside of the HPE Web site 

As per my understanding if thin provisioning feature is needed NTFS should be used. Any operating system experts can confirm that. 

[IMPI-Ced]

Hi  ArunKKR,

thanks for you reply.

In fact no thin provisionning : the MSA is connected to the server using SAS, then in DAS mode.

No hypervisor, the windows is installed directly on the server and sees the MSA as a local disk.

Veeam is using this disk directly.

I'm still under tests, but it seems that disabling defrag is the clue (i still do now know why it is enabled by default on reFS !!)

I'll wait for one or two week to be sure and update this thread

[IMPI-Ced]

Just to keep updated : i'm recovering space, little by little, but i went from 9 TB free to 15 TB free

We should be sure the problem was about defrag next week

[mr_vaughn]

Which method is being successful in recovering the space?

Did you switch to NTFS?

[IMPI-Ced]

HI mr_vaughn,

it seems that disabling scheduled defrag did the trick. In fact i read that defrag on reFS could "split" dedup block and then use many space.

By the way i never schedulted it, it means that MS defrag is scheduling defrag by default, even on reFS volume which is weird !

I do not want to switch to NTFS as i'm using Veeam that really takes advantage of dedup from reFS.

But lets wait on week or two to be really sure

[IMPI-Ced · Accepted solution]

Hi,

as promised i come back with news. And good ones !

This is indeed the defrag (scheduled during the install of windows, i never did it) on the refs that was "broking" the dedup and eating space.

I waited for some weeks for old un-deduplicated vbk and vib to disappear and to be replaced by the new deduplicated ones.

On 55 TB volume i had 3TB free, i now have 20 TB (and i also increased retention on some backup !)

Ced

[Sunitha_Mod]

Hello @IMPI-Ced,

That's Excellent! 

We are glad to hear you found the solution and we appreciate you for keeping us updated. 

[Gotthard_Anger]

Hello,

that´s an interesting result. We have the same environment. Howto disable the defrag on the repository drives?

With regards

Go

[Gotthard_Anger]

Found it,
https://answers.microsoft.com/en-us/windows/forum/all/disable-ssd-disk-defragmentation-forever/e9abdc3c-e018-441e-ac4c-585df62e17de

with regards

Gotthard

[IMPI-Ced]

Sorry for replying too late

I did it very simply : on drive il right-clic/properties, tools tab., then i went on optimize and at the bottom i chnaged the scheduled defrag

HTH

Regards

Cédric