Virtualization Platforms - A Brief Background

Virtualization has been around since the 1960s, but it wasn't till Intel and AMD started introducing hardware acceleration features that the feature started gaining mainstream focus outside enterprise applications. In addition to several applications in the enterprise space, virtualization has also started to lower the cost of IT infrastructure even for SMBs (think in terms of virtualized Exchange servers and similar applications). However, does the current state of virtualization offer any applications / benefits to home users? What are the ways in which regular users can take advantage of it? The answer to the second question is partly provided by QNAP's Virtualization Station package in the TS-x51 series. The answer to the first question will decide whether the Virtualization Station package can offer compelling enough benefits for users to choose the QNAP TS-x51 series over competing models from other vendors.

Put simply, the virtualization concept that we are discussing today refers to the creation of computing resources that exist 'virtually' - i.e, independent of the underlying hardware infrastructure. Most commonly, the creation of a virtual machine (VM) implies the setting up of a computer (guest machine) on certain hardware resources (host machine) such that the software / OS being run on the VM is separated from the host's hardware resources. An example could be the setting up of a Linux distribution as a VM on a computer running Windows as the host OS. Software developed for Linux can be run on the VM. The combination of hardware and software on the host machine which enables the creation and running of VMs is called as the hypervisor.

Hypervisors come in two flavours: bare-metal and hosted. While bare-metal solutions install directly on the hardware (VMware ESXi, Citrix XenServer and Microsoft Hyper-V), hosted ones run on top of a host OS. As examples of the latter, we have Oracle VM VirtualBox, QEMU and Hyper-V for Windows. QNAP's Virtualization Station is also a hosted hypervisor. It is based on QEMU (determined by taking a look at the running processes in the QNAP TS-451 with a VM active). We have already looked at the performance aspects of the TS-451 in an earlier review.

QEMU powers almost all of the Linux-based virtualization technologies. It takes advantage of the hardware-level support in processors (an additional reason why QNAP's Virtualization Station is supported only on models with CPUs supporting VT-x capabilities).

Readers interested in learning more about virtualization (particularly from a SMB / SME viewpoint) can peruse our articles focused on that market segment. In the rest of this write-up, we will take a detailed look at QNAP's Virtualization Station, followed by a hands-on report of how it works in the TS-451. One of the unique features of QTS 4.x is the support for SMB 3.0. We take this opportunity to evaluate SMB 3.0 support in the process of determining the performance impact of running a VM on the TS-451. We will also talk about power consumption numbers in the concluding section. Prior to all that, we take a look at the testbed infrastructure for evaluating performance as well as long term usage.

Performance Evaluation Setup

The QNAP TS-451 can take up to four drives. The benchmarks presented later in this review are with the unit configured in RAID 5 using four Western Digital WD4000FYYZ RE drives as the test disks.

AnandTech NAS Testbed Configuration
Motherboard Asus Z9PE-D8 WS Dual LGA2011 SSI-EEB
CPU 2 x Intel Xeon E5-2630L
Coolers 2 x Dynatron R17
Memory G.Skill RipjawsZ F3-12800CL10Q2-64GBZL (8x8GB) CAS 10-10-10-30
OS Drive OCZ Technology Vertex 4 128GB
Secondary Drive OCZ Technology Vertex 4 128GB
Tertiary Drive OCZ Z-Drive R4 CM88 (1.6TB PCIe SSD)
Other Drives 12 x OCZ Technology Vertex 4 64GB (Offline in the Host OS)
Network Cards 6 x Intel ESA I-340 Quad-GbE Port Network Adapter
Chassis SilverStoneTek Raven RV03
PSU SilverStoneTek Strider Plus Gold Evolution 850W
OS Windows Server 2008 R2
Network Switch Netgear ProSafe GSM7352S-200

The two ports of the TS-451 were link aggregated in 802.3ad LACP to create a 2 Gbps link for the cases in which no VM was active. In the active VM case, one of the network ports gets dedicated to the VM, while the other is reserved for NAS use. Our performance evaluation testbed configuration is outlined above.

Long Term Evaluation Setup

Usage of WD Re drives and Netgear's GSM 7352S switch make sense for benchmarking purposes, but hardly reflect the general use-case of the QNAP TS-451.

In order to simulate day to day usage, we utilized four WD Red hard drives in a RAID-5 configuration. The performance, as expected, doesn't scale up to what can be obtained with the Re drives, but that is hardly required for most applications of the TS-451.

Thank You!

We thank the following companies for helping us out with our NAS testbed:


QNAP's Virtualization Station
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  • bsd228 - Tuesday, August 19, 2014 - link

    The advantage of having the VM on the filer is that you're not transferring the data twice (not really a concern for the mtdaap server, but more so for the streaming HD video). And with Haswell cpus now taking the same sort of power draw as recent year Atoms and ARMs, you have this cpu capacity for nearly the same energy cost. But that makes more sense on a bigger box that this one. The only point to a single VM option is to support one app class/OS that QNAP doesn't offer natively.
  • Solandri - Monday, August 18, 2014 - link

    I built my own combo NAS/VM server after a lot of research. After running it for 3 years, the two (opposing) key points to me are:

    - Starting with Sandy Bridge, the i5 and i7 Intel CPUs are extremely efficient at idle. You can put them into a 24/7 device like a NAS and they won't cost you substantially more in electricity than a regular NAS. Yet they will have lots of processing power on tap for the occasions when a VM needs it. The Celeron in the TS-451 really isn't appropriate for this type of device. Almost the same idle power, much less peak processing power.

    - There is something to be said for keeping your NAS separate from your VMs. It's rare, but I have had a VM crash or hang the hypervisor (ESXi). I only use this at home so it's no big deal when this happens. But in something like a small business environment, I would recommend they be separate devices. Just to be safe.

    Learning to use the hypervisor is a bit of a pain, but once you get it down you don't need to be a sysadmin wannabe. After the initial install, ESXi can be controlled entirely with a GUI. I only run one Linux VM (for playing around with), and a FreeNAS VM (FreeBSD) which quite frankly is fire and forget. The rest are Windows VMs (and one OS X VM) for various things I want to keep separate from my personal laptop. e.g. One VM is for CPU-heavy tasks like re-encoding videos, so I can encode "on my laptop" without killing my laptop's battery life. Another is for running my home business, which prevents exposing that VM to whatever malware I might accidentally pick up from browsing websites and trying out new software.

    This isn't the only way to skin this cat. I'm contemplating moving most of the VMs to my laptop. Do my general web browsing in one VM, my secure browsing like banking in another, and installing all my apps in another VM so I don't have to reinstall every time I upgrade laptops. Games would be the only apps which run natively. So I'm not saying a combo NAS/VM server is the be-all end-all solution. It's just an option which may suit some people better than others.
  • deeceefar2 - Monday, August 18, 2014 - link

    As someone who is a linux sys admin and a small business owner. I can testify that this product is pretty much right on the money. Time is VERY limited when you run a small business and there is very little time to do IT even when you know how to do it. In the time it would take for me to configure any OS to do what this has out of the box, it would cost me far more in billable time then I would ever make up in cost savings. I used 2 of these to make sure our files would always be operational, and then we used dropbox syncing. There are more ways I could have accomplished that now. This has a virtual machine which can be used to provide a domain server for the network. I use it for visual studio development from my laptop at home so I don't have to deal with switching context on my macbook. SOO many uses for this out of the box. In a corporate environment it may not fit, but anything smaller this is a huge cost savings, and just works.
  • mattlach - Tuesday, August 19, 2014 - link

    If it only has the capability to run 1 VM (and with this little RAM, thats really all it can handle), then what is the point? Run bare metal. This is just silly.

    I'm sorry, but only misguided home/power users are going to buy something like this. If you are a power user you know your stuff, and instead you'll build a real capable ESXi whitebox to use for NAS and virtualization and forgo this cute little consumer style prepackaged crap.

    Heck, for about the price of this thing, I just bought a used 12 bay HP ProLiant DL180 G6 with dual 6 core Xeon L5640's and 64GB of registered ECC ram to use as my new basement NAS/Virtualized server.

    This thing is completely pointless IMHO.
  • ganeshts - Tuesday, August 19, 2014 - link

    Power consumption? Transcoding capabilities? As I said in another comment, you have to consider the whole package together when deciding on whether to go with the TS-x51 series, not just its virtualization features.

    I definitely agree with the sentiment that this is not for everyone, but will definitely not say that there is no target market for this. I am quite sure there are plenty of prospective consumers who haven't even cared about what virtualization is, or how to use it to their benefit - For those users, this definitely is a gentle introduction into that world.

    Btw, for your used unit - do you have support personnel? RMA capabilities? All those are major factors in pricing a COTS NAS. In my opinion, you are comparing apples and oranges.
  • beginner99 - Tuesday, August 19, 2014 - link

    Target market? I could use it as a NAS and a web server for example. No need to get 2 devices. That would cost more no doubt.
  • nafhan - Tuesday, August 19, 2014 - link

    Actually, it'd probably do pretty well in a SOHO environment, especially running several smaller (maybe Linux?) VM's. The thing with servers in a smaller environment is they are often ripe for consolidation as they are almost never fully utilized. You could probably over-provision the memory and CPU resources on this thing (in many use cases) and it probably be completely transparent to the end users. And if office space is at a premium, you'd be taking 4 or 5 boxes and turning it into one.

    The real question in my mind is why you'd pick this over doing something similar with cloud services...
  • Arnok666 - Saturday, October 17, 2015 - link

    Some areas have crappy internet, so cloud is out, plus who wants to give away all their data?
    What happens when internet goes down ?
    The power usage for this is significantly lower than even a PC with a 250w power supply.

    I am looking forward to this, and put my $4k Intel Server up for sale since i can run a couple VM's on this, which is all i need .. not a 750 watt server mostly idling all the time...
  • Gigaplex - Monday, August 18, 2014 - link

    SMB 3.0 support? Do they use a patched Samba or do they have a fully custom stack? I'd like to get my hands on the SMB 3.0 multichannel feature on my homebrew "NAS".
  • deeceefar2 - Monday, August 18, 2014 - link

    Interestingly I'm actually using mine for both Power Users Application Scenarios: 1 & 3.

    I have a TS-460-pro and I upgraded the processor to
    Intel Core i7-3770S and the ram to 16 GB KVR16S11K2/16. I can't say enough great things about the QNAP boxes I've had. From a small business perspective it can do pretty much everything you might ask of it.

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