Performance - Cache
QNAP introduced Cache Acceleration in QTS 4.0, but I again didn't notice it until 4.1. I had a 60 GB OCZ Agility 2 SSD in the parts pile, so I threw it in and configured it as cache for a three-drive RAID 0 volume. I used RAID 0 because I didn't want to wait the 6+ hours needed for a full RAID 5 resync. You can use a volume while it is resyncing, but I have to wait so that benchmarks tests aren't negatively effected.
I ran the standard benchmark suite with the cache enabled. The Hit Rate History plot shown in the screenshot indicates a peak of 35% cache hit rate, but there is no detailed reporting or history available beyond that little graph.
QNAP TS-470 Pro Cache Acceleration
The benchmark results show essentially the same performance in most cases. The NASPT Directory Copy and Content Creation benchmarks had the largest differences. But two of three benchmarks had lower performance with SSD cache enabled, the worst being a 32% throughput reduction in the NASPT Directory Copy To NAS (write) test.
|Benchmark||RAID 0||RAID 0 w/ cache||% Difference|
|Windows File Copy Write||109.67||108.31||-1|
|Windows File Copy Read||108.15||108.24||0|
|NASPT FileCopy To NAS||119.31||116.98||-2|
|NASPT FileCopy From NAS||112.75||112.14||-1|
|NASPT Directory Copy To NAS||12.27||8.34||-32|
|NASPT Directory Copy From NAS||14.99||16.15||+8|
|NASPT Content Creation||13.32||12.83||-4|
|NASPT HD Playback & Record||121.05||121.02||0|
|NASPT 4x HD Playback||113.22||112.00||-1|
Table 2: SSD Cache Acceleration Comparison
In the QTS 4.1 SMB user manual, QNAP cautions: "Not all applications can benefit from the SSD cache feature. Please make
sure that the SSD cache is supported by your applications". I know the NASPT benchmarks are specifically designed to prevent caching, so perhaps this wasn't a fair test. But it goes show that you can't just throw an SSD in, turn on caching and expect performance miracles.
We just tweaked the NAS Ranker so that it doesn't artificially score products differently when their real-world performance would prove otherwise. With that said, the TS-470 Pro ranked at #5 out of 75 products currently in the NAS database. This is right below the QNAP TS-1079 Pro, which also has an Intel i3 CPU and right above the Synology DS713+ Disk Station, which has a dual-core Atom D2700.
If the Ranker is filtered to show only four-bay NASes, then the TS-470 Pro comes out in the #1 spot, followed by Synology's DS412+, which like the DS713+ also runs on an Intel Atom D2700. If you don't care about 10GbE, then the Synology, at half the 470 Pro's price, is the obvious choice between the two.
NAS Ranker Performance summary comparison
If we are looking at just 10GbE performance, then we have only NETGEAR's ReadyNAS 716 and Thecus' N7710-G to compare. Since 10GbE performance isn't included in the NAS Ranker, we have to compare performance the old way via the charts. Because 10GbE doesn't do much when working with small files, the composite below looks at NASPT File Copy write and read.
10GbE NASPT File Copy performance comparison
This is a comparison among three Intel-based platforms, from the RN716's most powerful quad-core 2.5 GHz Xeon Ivy Bridge E3-1265Lv2 to the Thecus' 2.9 GHz dual-core Pentium G850, with the QNAP's dual-core i3-3220 in between. As you might expect, the ReadyNAS 716 comes out on top, but you'll pay a stiff price premium for that performance.
At around $1200, the TS-470 Pro is not going to be an impulse purchase for home or SOHO buyers. And that's without its optional $629 dual-port copper 10GbE card or any drives in the box.
If you're looking for a top-performance four-bay NAS and don't care about 10GbE, then Synology's DS412+ at around $600 would put much less strain on your wallet. If you want four bays and just gotta have 10GbE to go with it, then the TS-470 Pro is the only game in town for now.