|QNAP TS-870U-RP NAS Network Storage Server|
|Reviews - Featured Reviews: Network|
|Written by Bruce Normann|
|Tuesday, 04 June 2013|
Page 13 of 17
1GB RAID 5 Test Results
If you've got more than three HDD spindle to put in play, it makes sense to use one of the more advanced RAID configurations. RAID 5 is one of the most popular setups, primarily due to the balance it exhibits between capacity and redundancy. Not surprisingly, most NAS units that can support more than three HDDs also support RAID 5, so it makes sense to use it for test purposes. 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. I also took advantage of the massive capacity that the QNAP TS-870U-RP offers, and tested it with the full complement of eight drives. I am fortunate to have purchased eight W-D Caviar Black 750GB drives before the floods in Thailand wiped out half the world's HDD production capacity. I'm also showing results for three different NAS units with 10GbE interfaces, which really show the true capability of these larger models with more than four drive bays.
The top three bars in the RAID5 charts are the results for the TS-870U-RP. Normally, I arrange all the results in descending order, but with the mix of 8x HDD v. 4x HDD and GbE v. 10GbE, I thought it would be easier to understand this way. The fact is, the TS-870U-RP would have ended up on top, anyway. It's READ performance was outstanding, and there's probably more speed available with a more aggressive test protocol. All these results are based on a single workstation interfacing with the NAS, and the larger models in this group are designed to handle data requests from multiple servers at one time. That doesn't invalidate these results, because it's still important to know what level of performance is available for a single user, as well as the overall aggregate.
Before we look at the benchmark results, I want to show you the typical NAS CPU and Memory loading that occurred during these timed file transfer tests. As you can see, they are both quite low, and they stayed that way throughout the whole test. This chart is from a new widget that's included in the QFinder application, which you can put on your desktop to monitor system resources, network activity, etc. The old resource monitor screens are still available in the main software, and offer run charts instead of real-time "meters".
The 1 GB RAID 5 disk write test shows very strong results, as well. Even though the TS-870U-RP doesn't take top honors like it did in the Read tests, it provides nearly 95% of the performance of the top two models. Performance scaling was also similar to the read results, as the NAS configuration went from four disks to eight, and from GbE to 10GbE. It's well known that RAID 5 write performance can be a weak point, with all the computation overhead involved and the extra parity bits that need to be calculated and written to each of the drives. The only way to overcome that is with raw computational horsepower, and there may have been concerns that the Celeron CPU in the TS-870U-RP wouldn't be up to the task. These results clearly show that QNAP made wise choices when designing the TS-x70 platform. They picked the lowest cost CPU that would meet the performance requirements and keep up with the rest of the system. Of the two other 8-bay NAS models, the EonNAS consistently did better in Write tests than Read, and it turns in a top tier performance here. Both of the QNAPs had more balanced performance and usually were able to read data faster than they could write it to disk. Still, there's not a lot to complain about, with the top three systems reaching between 420 and 450MB/s Write speeds.
Next up is 10 GB (1000 metric megabytes / 10,000,000,000 bytes) file transfer testing. Using the 4 and 8-disk RAID 5 configuration in each NAS, and a combination of 10GbE and single Gigabit connections, network throughput will be put to the test, and the effect of any system or hardware caches will be minimized. This is almost pure sequential disk access testing, combined with a real-world application that gets repeated millions of times a day - file transfer.
10GB RAID 5 Test Results
Looking at Read tests with a single 10GB file, the TS-870U-RP extends its dominance in Read performance. The Read results with a single 10GB file almost reached 600 MB/s, completely eclipsing the performance of any other system I've ever tested before. No worries about the new "budget" rack mount series not having enough performance under the hood, that's for sure. The performance scaling was consistent again, as the number of disks increased and the network bandwidth opened up the bottleneck that we usually see when NAS units are constrained by their GbE connections. The bottom half of this chart is filled with NAS products that could post much better numbers in this benchmark, if only they were equipped with better network interfaces.
Looking at write tests with a single 10GB file, the TS-870U-RP comes out in second place, tightly sandwiched between the more costly TS-879U-RP and the EonNAS 850X models. I used to say that if you're writing large files to a NAS, you can't afford to scrimp on system hardware; you need the biggest, baddest CPU you can afford. This Celeron-based NAS has made me re-think that a bit, in favor of a more optimized systems approach. Clearly, the 10x improvement in network bandwidth that you get with 10GbE is a critical factor in getting the maximum available performance from a high-capacity NAS. There are a number of other elements that must actively support the system as well, like the Platform Hub Controller (nee Southbridge) and SATA-to-PCI interfaces. In addition, the Operating system has a big influence, as we've seen lately with a couple of NAS units that feature a Solaris based O/S. The TS-870U-RP has just the right blend of components to maximize the performance v. cost equation, which was the main design brief for this whole new series from QNAP.
All in all, after these series of file transfer benchmarks, I have to give a lot of credit to QNAP for delivering the goods on their marketing message for the new TS-x70 series, "Economical, yet Powerful..." It's the first NAS I've ever seen break 500MB/s, and it did it with a Read speed of almost 600 MB/s. That's faster than many SSDs...! If you combine this NAS with some of the new economical 10GbE switches, like the NETGEAR XS708E ProSafe Plus 10GbE Switch I just reviewed, the potential is there to radically improve the productivity of the high-end workstation user, at a much lower cost than was recently possible. With such a wide performance envelope, it's suited for any task you might think of: front-line storage, backup, replication, or any combination. Its iSCSI capability means you're not limited to a single application, and the compatibility with multiple virtualized environments will be a big plus for corporate users.
We may see different results as we look at other tests, because these 1GB and 10GB files used in this portion of testing are much larger and more highly compressed than what a typical SOHO would feed their NAS. That's one reason Benchmark Reviews has expanded our testing protocol for NAS systems, to use a wider range of test data that's already in common use. Let's take a look at one of those tests, developed by Intel specifically for testing NAS devices. Oddly enough, it's called the "Network Attached Storage Performance Test"; NASPT for short.
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