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QNAP TVS-863+ vNAS Server Review

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Network Terminology

Benchmark Reviews primarily uses metric data measurement for testing storage products, for anyone who is interested in learning the relevant history of this sore spot in the industry, I’ve included a small explanation below:

The basic unit data measurement is called a bit (one single binary digit). Computers use these bits, which are composed of ones and zeros, to communicate their contents. All files are stored as binary files, and translated into working files by the Operating System. This two number system is called a “binary number system”. In comparison, the decimal number system has ten unique digits consisting of zero through nine. Essentially it boils down to differences between binary and metric measurements, because testing is deeply impacted without carefully separating the two. For example, the difference between the transfer time of a one-Gigabyte (1000 Megabytes) file is going to be significantly better than a true binary Gigabyte (referred to as a Gibibyte) that contains 1024 Megabytes. The larger the file used for data transfer, the bigger the difference will be.

Have you ever wondered why your 500 GB hard drive only has about 488 GB once it has been formatted? Most Operating Systems utilize the binary number system to express file data size, however the prefixes for the multiples are based on the metric system. So even though a metric “Kilo” equals 1,000, a binary “Kilo” equals 1,024. Are you confused yet? Don’t be surprised, because even the most tech savvy people often mistake the two. Plainly put, the Kilobyte is expressed as 1000 bytes, but it is really comprised of 1,024 bytes.

Most network engineers are not fully aware that the IEC changed the way we calculate and name data chunks when they published the new International Standards back in December 1998. The International Electrotechnical Commission (IEC) removed the old metric prefixes for multiples in binary code with new prefixes for binary multiples made up of only the first two letters of the metric prefixes and adding the first two letters of the word “binary”. For example, instead of Megabyte (MB) or Gigabyte (GB), the new terms would be Mebibyte (MiB) or Gibibyte (GiB). While this is the new official IEC International Standard, it has not been widely adopted yet because it is either still unknown by institutions or not commonly used.

NAS Testing Methodology

All the NAS devices we test cannot accommodate all the different disk configurations, so our current test protocol has typically been based on two of the most popular setups: a basic (single) disk and RAID-5 configurations. Most NAS products that can support RAID 5 go beyond the minimum number of drive bays, to a total of four, so that is the number of drives that I typically use to test with, even though I could get by with only three. During initial setup, I checked the NAS firmware by looking at the binary files from QNAP’s website. The installed firmware was only one version behind the latest, and was approximately two months old. The release notes indicated very minor changes between the two versions, but I decided to upgrade anyway. QNAP makes the firmware update process quite painless and foolproof, and they have always provided honest and comprehensive release notes. If something was wrong or is wrong, they list it. I connected the TVS-863+ NAS directly to an Intel X520-T2 10Gbps Ethernet NIC in the test-bench system, with a ten-foot CAT6 patch cable. I set up a static IP address on the host PC, consistent with the default address of the Turbo NAS unit, and we were in business.

With the networking taken care of, the next potential bottleneck that needed attention is the disk system on the host PC. In previous tests, I relied on the third generation OCZ Agility SSD, which is good for at least 500 MB/s, input or output, on the appropriate Intel Platform Controller Hub. I decided it was time to bypass the SSD on the test rig and install a RAM Disk. There are at least a dozen products on the market that will create and manage a RAM Disk on Windows systems; I chose RAMDisk v3.5.1 from Dataram based on performance tests in several reviews (we read ’em, too….) and its reasonable cost structure. I assigned 10GB of space to the RAM Disk, in order to replicate the test protocol I’ve been using for all my NAS testing. One other trick was necessary to get the RAM Disk to transfer files larger than 2GB. I had to use the “Convert” utility in Windows to make the RAM Disk into an NTFS volume. Then I was able to perform the file transfers with 10GB files, no problem. If you want to avoid this extra step, be sure to look for a RAM Disk product that directly supports the NTFS file system.

QNAP_TS-470_Turbo_NAS_Server_35-Dataram_RAMDisk

For basic throughput evaluation, the NAS product received one test transfer followed by at least three timed transfers. Each test file was sent to the Seagate 4TB NAS HDD (ST4000VN000) hard drives installed in the NAS for a timed NAS write test, and that same file was sent back to the RAM Disk in the test system to perform a NAS read test. Each test was repeated several times, the high and low values were discarded and the average of the remaining results was recorded and charted. I used these new Seagate NAS drives in my last test, with the QNAP TS-451 Turbo NAS, as they were supplied and installed by the manufacturer. They worked well, and I saw no difference in test results that I could attribute to the slower spindle speed of these drives. They run at 5900 RPM, vs. the 7200 RPM of the WD Black drives that I used to use. With the higher areal density of the 4TB NAS drives, I suspect the RPM difference is completely neutralized in use. Any minor variation in speed of the HDDs will probably be dwarfed once the SSD Cache is in operation anyway.

The Read and Write transfer tests were conducted on each NAS appliance using the 1 GB file and then a 10 GB file. A second set of tests are conducted with Jumbo Frame enabled, i.e. the MTU value for all the Ethernet controllers is increased from 1500 to 9000. Most of the NAS products tested to date in the Windows 7 environment have supported the Jumbo Frame configuration. Over the course of several years of testing, the Jumbo Frame configuration has slowly become the dominant performer. In the early days there was some inconsistency, but that’s all been cleared up with improvements in the firmware for the Ethernet chips used by the NAS manufacturers. I used a single Ethernet connection for all tests; I have not been able to achieve consistent results with various units using the IEEE 802.3ad Link Aggregation Control Protocol (LACP) mode, and I didn’t need the fail-over redundant connection for my testing. The TVS-863+ comes standard with two GbE ports and one 10GbE port carried on a factory-installed adapter card. My test bench PCs use consumer operating systems (Win7), which lacks full support for LACP, but they all run 10GbE like a champ.

I also run the Intel NAS Performance Toolkit (NASPT) version 1.7.1, which was originally designed to run on a Windows XP client. People smarter than me have figured out how to run it under Windows 7, including the 64-bit version that is used more often than the 32-bit version these days. NASPT brings an important perspective to our test protocol, as it is designed to measure the performance of a NAS system as viewed from the end user’s perspective. Benchmarks like ATTO use Direct I/O Access to accurately measure disk performance with minimal influence from the OS and the host platform. This provides important, objective data that can be used to measure raw, physical performance. While it’s critical to measure the base performance, it’s also important to quantify what you can expect using real-world applications, and that’s exactly what NASPT does. One of the disadvantages of NASPT is that it is influenced by the amount of memory installed on the client, and it was designed for systems that had 2-4 GB of RAM. Consequently, two of the tests give unrealistic results, because they are measuring the speed of the buffer on the client, instead of the actual NAS performance. For that reason, we will ignore the results for “HD Video Record” and “File Copy to NAS”. I’m also not going to pay too much attention to the “Content Creation” test, as it is too heavily focused on computing tasks that aren’t typically handled by the NAS.

QNAP TVS-863+ Turbo vNAS Server NASPT-9000-NoSSD-NoCRYPT-R5

Benchmark Reviews also measures NAS performance using some throughput tests that are traditionally used for internal drives. The ATTO Disk Benchmark program is widely recognized and offers a comprehensive set of test variables to work with. In terms of disk performance, it measures transfer rates at various intervals for a user-specified length and then reports read and write speeds for these spot-tests. CrystalDiskMark 3.0 is another file transfer and operational bandwidth benchmark tool from Crystal Dew World that offers performance transfer speed results using sequential, 512KB random, and 4KB random samples. Benchmark Reviews uses CrystalDiskMark to illustrate operational IOPS performance with multiple threads, which allows us to determine operational bandwidth under heavy load. The sequential file transfer test is the most relevant one for NAS products, and that’s the one we report on, although I tend to run the full test suite just in case I need the data at a later date. I was also very interested to see how well the SSD Cache could improve on the random access test components.

QNAP TVS-863+ Turbo vNAS Server Crystal-9000-2xSSD-NoCRYPT-

We are continuing our NAS testing with the exclusive use of Windows 7 as the testing platform for the host system. The performance differences between Win7 and XP are huge, as we documented early on in our QNAP TS-259 Pro review. The adoption rate for Win 7 has been very high, and Benchmark Reviews has been using Win 7 in all of our other testing for some time now. I know there are some XP holdouts, and I admit to using it for select applications, but the modern household has caught up with the 21st century, and any PC connected to the network will be running Win7 at a minimum.

NAS Comparison Products

Support Equipment

  • (4) Seagate NAS HDD, ST4000VN000, 4 TB, 5900 RPM, 64MB Cache, SATA 6.0Gb/s, 3.5″
  • (4) Western Digital Caviar Black WD7502AAEX 750GB 7200 RPM 64MB Cache SATA 6.0Gb/s 3.5″
  • (2) OCZ Agility3 SSD 120GB (AGT3-25SAT3-120G)
  • Intel E10G42BT, X520-T2, 10Gbps Ethernet NIC, PCIe 2.0 x8, 2x CAT6a
  • Dataram RAMDisk v3.5.1.130R22
  • Intel NAS Performance Toolkit (NASPT) version 1.7.1
  • ATTO Disk Benchmark v2.47
  • CrystalDiskMark 3.0
  • 10-Foot Category-6 Solid Copper Shielded Twisted Pair Patch Cable
  • 1 metric Gigabyte Test File (1 GB = 1,000,000,000 bytes)
  • 10 metric Gigabyte Test File (10 GB = 10,000,000,000 bytes

Test System


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