ASRock Rack C2750D4I and U-NAS NSC-800: A DIY File Server

Introduction and Testing Methodology

Small businesses and power users in a home setting have begun to face challenges with managing large amounts of data. These are generated either as part of day-to-day business operations or backing up of multimedia files from phones / tablets / TV recordings etc. One option is to use a dedicated COTS (commercial off-the-shelf) NAS from a vendor such as Synology or QNAP. Sometimes, it is also necessary to have a file server that is much more flexible with respect to programs that can be run on it. This is where storage servers based on Microsoft's offerings or even units based on Linux distributions such as Red Hat and Ubuntu come into play. These servers can either be bought as an appliance or assembled in a DIY fashion. Today, we will be looking at a system based on the latter approach.

A DIY approach involves selection of an appropriate motherboard and a chassis to place it in. Depending on the requirements and motherboard characteristics, one can opt for ECC or ordinary RAM. The platform choice and the number of drives would dictate the PSU capacity. The file server being discussed today uses the ASRock C2750D4I mini-ITX motherboard in a U-NAS NSC 800 chassis. 8 GB of ECC DRAM and a 400 W PSU round up the barebones components. The table below lists the components of the system.

Evaluation Methodology

A file server can be used for multiple purposes, unlike a dedicated NAS. Evaluating a file server with our standard NAS testing methodology wouldn't do justice to the eventual use-cases and would tell only a part of the story to the reader. Hence, we adopt a hybrid approach in which the evaluation is divided into two parts - one, as a standalone computing system and another as a storage device on a network.

In order to get an idea of the performance of the file server as a standalone computing system, we boot up the unit with a USB key containing a Ubuntu-on-the-go installation. The drives in the bays are configured in a mdadm RAID-5 array. Selected benchmarks from the Phoronix Test Suite (i.e, those benchmarks relevant to the usage of a system as a file server) are processed after ensuring that any test utilizing local storage (disk benchmarks, in particular) point to the mdadm RAID-5 array. Usage of the Phoronix Test Suite allows readers to have comparison points for the file server against multiple systems (even those that haven't been benchmarked by us).

As a storage device on a network, there are multiple ways to determine the performance. One option would be to repeat all our NAS benchmarks on the system, but that would be take too much time to process for a given system that we are already testing as a standalone computer. On the other hand, it is also important to look beyond numbers from artificial benchmarks and see how a system performs in terms of business metrics. SPEC SFS 2014 comes to our help here. The benchmark tool is best used for evaluation of SANs. However, it also helps us here to see the effectiveness of the file server as a storage node in a network. The SPEC SFS 2014 has been developed by the IOZone folks, and covers evaluation of the filer in specific application scenarios like the number of virtual machines that can be run off the filer, number of simultaneous databases, number of video streams that can be simultaneously recorded and the number of simultaneous software builds that can be processed.

Our SPEC SFS 2014 setup consists of a SMB share on the file server under test connected over an Ethernet network to our NAS evaluation testbed outlined below. Further details about the SPEC SFS 2014 workloads will be provided in the appropriate section.

The above testbed runs 10 Windows 7 VMs simultaneously, each with a dedicated 1 Gbps network interface. This simulates a real-life workload of up to 10 clients for the NAS being evaluated. All the VMs connect to the network switch to which the NAS is also connected (with link aggregation, as applicable). The VMs generate the NAS traffic for performance evaluation.

Thank You!

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

• Thanks to Intel for the Xeon E5-2630L CPUs and the ESA I-340 quad port network adapters
• Thanks to Asus for the Z9PE-D8 WS dual LGA 2011 workstation motherboard
• Thanks to Dynatron for the R17 coolers
• Thanks to G.Skill for the RipjawsZ 64GB DDR3 DRAM kit
• Thanks to OCZ Technology for the two 128GB Vertex 4 SSDs, twelve 64GB Vertex 4 SSDs and the OCZ Z-Drive R4 CM88
• Thanks to SilverStone for the Raven RV03 chassis and the 850W Strider Gold Evolution PSU
• Thanks to Netgear for the ProSafe GSM7352S-200 L3 48-port Gigabit Switch with 10 GbE capabilities.