|QNAP TS-879U-RP NAS Network Storage Rack Server|
|Reviews - Featured Reviews: Network|
|Written by Bruce Normann|
|Tuesday, 07 February 2012|
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Technology Details: QNAP TS-879U-RP Turbo NAS
The biggest chip on the board is the Intel Core i3-2120 CPU, a dual-core member of the new Sandy Bridge family. It's certainly got the biggest heatsink, that's a finned aluminum block held in place by four heavy-duty springs. As much work as the CPU does, it's isolated from directly communicating with most of the subsystems by the Intel Platform Controller Hub, which we all used to call the Southbridge (back when there was also a Northbridge...). This is the second hardest working chip on the main board, and it's also got a heatsink on top, although it's less that 1/10 the size of the one on the CPU. Although the Core i3 CPU in the TS-879U-RP does not have it, some models in the QNAP TS-x79 product line have native CPU support for the Advanced Encryption Standard New Instructions (AES-NI) set. These new instructions speed up the encryption/decryption process by anywhere from 3x to 10x, depending on the implementation. As slow as the Atom-based and Marvell-based models are with encryption enabled, the QNAP TS-x79 models are the minimum level that can realistically support AES 256-bit Volume-based data Encryption. All of the NAS models I've tested to date have been bottle-necked by their CPU during RAID Write operations, and the extra load of data encryption was just too much to handle. I'm curious to see how this vastly superior CPU will perform, even without the new instruction set.
Marvell supplies several ICs on the main board, and the SATA backplane board. They are marked 88SE9125, and are the interface between the PCI-Express lanes and the SATA devices. Each controller supports two 6 Gb/s SATA interface ports and a one-lane 5.0 GT/s PCIe host interface back to the Intel PCH. There are several of these controllers, located both on the main board and the SATA backplane, which is the same way they were deployed on the TS-659 Pro II that Benchmark Reviews tested last year. There is a whole family of parts in this series, and this one is optimized for use with a central RAID controller on the system board. Benchmark Reviews has reported on a number of issues in the past year, where a variety of brand new SATA 6Gb/s controllers aren't fulfilling the promises made for this interface. With the latest SSDs pushing more than 4Gb/s on both read and write cycles, many controllers aren't keeping pace. I anticipate the primary usage of the TS-879U-RP as being paired with traditional 3.5" HDDS, none of which operate anywhere near the full capabilities of the SATA 6Gb/s interface. With the right SSDs installed, the theoretical throughput for all of the drives running together would be well over 30 Gb/s, and the rest of the hardware (not to mention the rest of the IT world) just isn't ready for that, yet.
The Xilinx XC3S50A IC on the SATA backplane board is a Field Programmable Gate Array chip, which is basically a programmable logic device that can do anything you want it to. Their main advantage in the marketplace is that they can be developed and deployed quicker and much more cheaply than Application Specific ICs (ASICs). The graphics processor in a video card is a common example of an ASIC, and most of you know how long they take to develop and how much they can cost! In this case, I'm betting that this FPGA is the core RAID controller for the whole system, since I don't see any other devices on the PC board that are designed for that task.
The rest of the major ICs in the system are for power management, and for supporting the various interconnects, like USB, eSATA, and GbE. Intersil supplies their ISL6364C and ISL 6314C to provide multi-phase PWM control over the Voltage Regulator Modules that feed the CPU, RAM, PCH, etc. Renesas Electronics (nee NEC) provides their ubiquitous D720200F1 chip for USB 3.0 duties.
QNAP relies heavily on Intel for their Ethernet controllers in the high-end models of their product line. It's a smart move, as Intel is a leader in this area, even though they're not very well known for it by the public. Two different ICs combine forces to provide the MAC and PHY functions; the WGG82574L and the WG82579LM. The latter chip was just launched in 1Q2011, so both Intel and QNAP are keeping things current in this area. We'll see later, in our RAID testing, just how critical Ethernet performance is to a product like this.
To measure isolated NAS power consumption, Benchmark Reviews uses the Kill-A-Watt EZ (model P4460) power meter made by P3 International. I had both of the redundant power supplies plugged in to the meter, because that's the way 99.99% of users will run a device like this. Obviously, power consumption is going to depend heavily on the number and type of drives that are installed. The power draw also depends heavily on the fan speed that's required to keep the unit cool. When the device first starts up and the fans are going 100%, 215 W is consumed at first, then it tapers down to 165W. Once the system completes its boot process, and gets into idle standby mode, the QNAP TS-879U-RP consumed 133 watts of electricity. This is right in line with the 130W specified by QNAP for a system with eight 1TB drives installed. With all eight drives installed and during heavy file transfer operations, it drew 155W. When the system goes into Sleep Mode and spins all the drives down, the power is reduced to 84 watts. When the unit is turned off, it still consumes 7W in Vampire mode; be aware that even when it's turned off, the two SMPS modules still pull a small amount of power.
We've seen the ins and outs of the hardware, the new software, and the technology under the hood; now let's take a detailed look through the extensive list of features that you get with most every QNAP Turbo NAS. I know the next couple of sections are overly long, but it's critical to understand just how much these units can do. You don't want to be fooled into thinking it's just a big box full of drives. It's capable of so much more than that.