SMB 3.0 Evaluation and VM Performance Impact

QNAP's QTS 4.x is the only COTS NAS operating system that we are aware of with SMB 3.0 support. As a bit of a background, SMB 3.0 was introduced with Windows 8 and Windows Server 2012 as an update to the file-sharing protocol used in Windows systems. It brought in a number of changes including SMB Direct Protocol and SMB Multichannel. Security enhancements such as end-to-end encryption and a new AES-based signing algorithm also make it attractive for usage in business enviromnents.

QTS allows for setting of the maximum allowed SMB version. While SMB 3.0 shares turned out to be accessible even in Windows 7, enabling the SMB Encryption feature for a Samba share while setting up the shared folder rendered it inaccessible (except under Windows 8 and Windows Server 2012). For our evaluation, we created a Windows 8.1 VM in our NAS testbed and repeated our usual NASPT / robocopy benchmarks on a plain SMB 3.0 share and one on which SMB encryption was enabled. In addition, we also repeated the test with the Windows 8.1 VM on the TS-451 active and being loaded with our heavy Internet browsing workload. The graph below presents our observations.

QNAP TS-451 SMB 3.0 Performance

At the very outset, it is clear that enabling SMB encryption causes a huge hit in performance. It appears that the limitation is on the encryption rate, which seems to be topping out at 20 MBps. In the more interesting case of VM vs. non-VM, we find that, with the VM active, there is definitely a loss in performance. However, we doubt that it is much of an issue for even power users in home scenarios. Obviously, the penalty is much bigger for multi-client scenarios since the network ports can't be link-aggregated any more. That said, most home users don't even have routers supporting 802.3ad link aggregation. For such consumers, with the help of Virtualization Station, the second network port of the QNAP TS-451 can actually be put to better use (as a dedicated link for a VM / 'computer') than just a failover link for the NAS.

Virtualization Station on the TS-451 Miscellaneous Aspects and Concluding Remarks


View All Comments

  • shodanshok - Monday, August 18, 2014 - link

    Hi Ganesh, thank you for the good review.

    However, I strongly disagree on the chosen Raid level: if you want to run a virtual machine at full speed, you should really use Raid10 rather then Raid5. The problem with Raid5 is that typical 4KB random writes will trigger full stripe read/modify/write, which will lead noticeable slower VM performance.

    I personally faced off this very problem some time ago, with a custom Linux mdraid build running some (5+) VMs: switching to Raid10 drastically boosted performance.

  • ganeshts - Monday, August 18, 2014 - link

    Thanks for the note. Most consumers buying the TS-451 are looking for optimal balance of performance and capacity. With 4x 4 TB drives, RAID-5 gives 12 TB of effective storage, while RAID-10 gives 8 TB. I agree that in performance sensitive use-cases, the appropriate RAID level must be chosen.

    Another reason for choosing RAID-5 is that it typically has the worst performance (along with RAID-6) making it a good test of stressing the I/O and other platform capabilities of different NAS models. All our NAS reviews use RAID-5 for comparative benchmarking even though it might not be a suitable RAID level for a particular application.
  • tuxRoller - Monday, August 18, 2014 - link

    So, xen but not kvm? You're doing your reader a disservice by ignoring the third most popular virt platform. Reply
  • kmob - Monday, August 18, 2014 - link

    Ganesh, thanks is as always for a very thorough yet readable feature.

    To consolidate some of my machines, I was weighing purchasing a 'dumb' NAS (like the QNAP or Synology) and a small i7 or Xeon box running ESXi. Digging into your research on this QNAP, I stumbled on articles about people upgrading the QNAP x70 series boxes with i7 or Xeon 1265 processors and RAM for some beastly VM performance on the NAS. This seems like an outstanding application of this QNAP Virtualization Station on more robust hardware at a reasonable price (for one box).

    Thanks for getting my gears turning! I just ordered a QNAP 670 and a Xeon 1265L v2.
  • coburn_c - Tuesday, August 19, 2014 - link

    This article is confusing and poorly written. You start off with paragraphs of patronizing explanation on virtual machines but never discuss this NAS box you are testing. The first hardware specs I see are of a test machine? I had to go to the manufacturer website to see what abysmal specs the NAS box actually had.

    As for the substance.. I've run ESXi on a nettop before.. it's great. I wouldn't run it on a nettop that's also running my net shares, especially not a SOHO one. More importantly, I wouldn't run some off-brand crap, I'd install ESXi.
  • ganeshts - Tuesday, August 19, 2014 - link

    Thanks for the note. Majority of the other comments on this review don't echo your sentiments (probably because they have already been through the first part of the TS-451 review where I had indicated that the review would be in three parts - and specifically mentioned that discussion of the virtualization aspects would be the second piece).

    I do agree that new readers might find it a bit confusing as to what the exact specs and performance of the TS-451 are. I have added this statement in the initial section for this purpose: We have already looked at the performance aspects of the TS-451 in an earlier review [ ].
  • wintermute000 - Tuesday, August 19, 2014 - link

    Its neat but I think its aiming for a pretty niche market.
    - want virt
    - dont want 'real' virt host
    - only want 1 low spec VM
  • DanNeely - Wednesday, August 20, 2014 - link

    With the single VM limit, IMO it's more about being able to run unofficial packages without risking your warranty by SSHing past the vendors front end interface and safeguards. Other than potentially trying to stop users from shooting themselves in the foot, the hard single VM limit doesn't make a lot of sense. While there's not enough hardware to run multiple heavy client OSes; you could run a several small headless *nix images to isolate applications before maxing the system out. Reply
  • Wisefoxx - Wednesday, August 20, 2014 - link

    Virtualisation station from Qnap is my first foray into VM's, I found it to be a fantastic addition to QTS. What's more with the 470 pro (4,6 or 8 bay) you can upgrade the processor to give you that little extra. I have a 45w i7 pro + 16gb ram installed and run multiple VM's. Such an upgrade path works well and gives you more confidence in the V-station platform. Reply
  • Insomniac - Thursday, November 27, 2014 - link

    Some people are reporting that they are able to run 16 GB of RAM (8 GB x 2) in the x51 series. Can you confirm that is true? Reply

Log in

Don't have an account? Sign up now