Storage Space vs Disk Management Mirroring

Windows 2012 R2:

I am deciding on a RAID 1 (Mirroring in Windows terminology) implementation. I understand I have two options included in Windows:

  • Storage Space Mirroring
  • Disk Management Mirroring

How does Storage Space compare Mirroring to Disk Management Mirroring?


Solution 1:

I have made some benchmarking on my home lab server using both technologies with two Samsung 850 PRO 512GB.

From what I can see, both mechanisms work the same way. Storage Spaces Mirroring performs better but consumes more CPU under diskspd benchmark, Dynamic Volumes Mirroring is a bit slower and obviously less CPU hungry.

Hope this helps you to decide what to go with.

Solution 2:

I just wanted to ask the same question, after doing some tests of my own, here are my findings.

I am not using SSDs but rather standard HDs.

Using the disk managagement mirroring seems to be a little faster. I used queue depth of 8 and came up with values for blocksize 512B, 8KB, 64KB and 4M in Atto Benchmarking Tool:

10M/15M, 140M/155M, 202M/200M, 200M/201M plain disk, only 1 partition

9M/20M, 140M/200M, 200M/200M, 200M/395M plain mirror in disk management, only 1 partition

7M/12M, 133M/151M, 200M/204M, 201M/377M storage pool storage space on first partition, others are a little slower

But.. to me that is neglible, since real performance depends on random I/O (where performance is more similar) and also if you access/share the drives through 1GBit/s network, in which case there is a limit at a little over 100MB/s anyway.

Most important for mirroring is the (rare) error case. So I also googled how to restore a broken mirror. There seems to be a large difference - for whatever reason.

Recovery seems very complicated for storage pool/storage spaces mirror:

https://technet.microsoft.com/en-us/library/dn782852%28v=ws.11%29.aspx?f=255&MSPPError=-2147217396

For disk management mirror it seems a lot easier

https://technet.microsoft.com/en-us/library/cc938519.aspx?f=255&MSPPError=-2147217396

So: disk management way was slightly faster (for me, on Windows Server 2016), plus recovery looks a lot easier. I did not use any cache-size tweaking or anything similar.

I also did not compare CPU usage, since I assume that high CPU and high I/O won't go together very often.

Originally, I also wanted to compare Starwind Virtual SAN and mirror across servers (creating a cluster) but I guess local mirror with backups will be good enough and the performance comparison with that is useless due to network bottleneck.