Performance - Competitive
As usual, the higher cache values compress the vertical scale in Figure 8, so you'll have to go to the table of values to really see what is going on. It's pretty clear that the NETGEAR is at the top of the heap, even at the larger cache-effect-free file sizes. The QNAP comes in in second place, maintaining a low-to-mid 40 MB/s speed from 512 MB file size on up.
In contrast, the 409+ stays right around 30 MB/s in the same file size range, while the 409 stays in the mid-20 MB/s. The Buffalo comes in last among the new-generation NASes across all file sizes and maintains a speed in the low-20MB/s range from 512 MB file size on up.
Figure 8: Competitive RAID 5 write comparison - 1000 Mbps LAN
Figure 9 compares the read performances, where, once again, the NVX produces the best results, ranging from 84 MB/s to 64 MB/s. The middle group is tougher to tell due to the significant performance drops shown by the Buffalo and DS409 as file sizes increase. But going by the calculated averages, the TS-439 Pro edges out the 409s with 64.3 MB/s vs. 60 MB/s. The Buffalo again brings up the rear with an average of 53 MB/s due to the very large drop in performance above the 256 MB file size.
Figure 9: Competitive RAID 5 read comparison - 1000 Mbps LAN
Performance - File Copy
The Vista SP1 1000 Mbps RAID 5 file copy write results in Figure 10 once again show that iozone results aren't the final word when it comes to measuring NAS speed. While the rankings are approximately the same, write speeds seem a bit lower and the NETGEAR NVX and QNAP TS-439 Pro swap #1 and #2 positions.
Figure 10: RAID 5 Vista SP1 File Copy Write
Figure 11 shows the 1000 Mbps RAID 5 File Copy read. Rankings are again the same as obtained using iozone, but speeds are generally higher, with the NVX topping the ranking at almost 100 MB/s!
Figure 11: RAID 5 Vista SP1 File Copy Read
Use the NAS Charts to further explore performance.
The new crop of RAID 5 NASes is making it tougher for NAS buyers in that the performance range is getting narrower, even though the hardware platforms are growing more diverse. Synology has stuck with Freescale for its higher-performance products, but the much-improved performance of the new Marvell-based platform is closing the gap between "economy" and "performance" versions.
In this case, I'm not sure that the $160 price premium for the 409+ is worth it. RAID 5 write performance is close enough to be a wash and you probably would not notice a difference if you were doing large backups to both products. On the other hand, you probably would see the difference in read performance if you were doing a lot of large file copies from both products. But if your reading is mostly in the form of HD video streaming, either product will do just fine.
I usually ding Synology for charging a premium price for its products. But this time, I have to say that both the 409 and 409+ are relative bargains, even when compared with the usual value leader: Buffalo. The least expensive price for the 2 TB Terastation III is $933 as I write this. If you subtract $240 for four WD 500GB Caviar Blue drives, that produces $693 for the base NAS. This is $100 higher than the $594 I find for the 409+ and $250 more than the 409, both of which are better performers.
If I do the same math for the NETGEAR NVX, which many say is overpriced, I subtract $640 for four Seagate Barracuda ES.2 1TB drives from the $1649 lowest price and get around $1000. This is almost a 170% premium over the 409+ and over a 225% markup from the 409. Although you do get a significant gain in RAID 5 performance from the NVX, you pay dearly for it.
The toughest choice could be between the 409+ and QNAP TS-439 Pro where the QNAP premium is around $200, RAID 5 file copy writes are better than the NVX's and reads are a significant step up from both 409s. And if iSCSI is on your must have list, then the QNAP has it, while the Synologys don't.
It's a tough choice all right, but kudos to Synology for making it that way with both the price and performance of its new 409s.