Refs intergrity streams?

[nmdange]

So I've noticed if you format a drive as REFS on Windows Server 2016, integrity streams are disabled by default now. At least on hardware raid/san volume. I'm not sure if the behavior is different with S2D since I don't have the hardware to test that.

I'm curious for other folks out there if they have integrity streams enabled/disabled on their ReFS backup repositories? Has anyone tested performance of Veeam backups with it set one way vs. the other? I'm leaning towards leaving it disabled when I have a hardware RAID controller that does its own integrity checking.

You can check if it's enabled by running the command

Code: Select all

fsutil fsinfo refsinfo <volume>

It will return info like this:
REFS Volume Serial Number : 0xf2be2842be280229
REFS Version : 3.1
Number Sectors : 0x000000027ffa0000
Total Clusters : 0x000000004fff4000
Free Clusters : 0x000000004f3a713a
Total Reserved : 0x000000000052700c
Bytes Per Sector : 512
Bytes Per Physical Sector : 512
Bytes Per Cluster : 4096
Checksum Type: CHECKSUM_TYPE_NONE

The last line will tell you if integrity streams are enabled or not. In this example it's not enabled. Also this example is a Hyper-V CSV so that's why the cluster size is 4K not 64K

[JammedFalcon]

If your hardware RAID controller is taking care of data integrity, there is no real need to turn additional integrity checks in ReFS, here's the blogpost which describes how ReFS works with different integrity checks settings: https://www.starwindsoftware.com/blog/refs-performance