Performance
The N5550 was tested with 2.03.04.atom firmware using our standard NAS test process.
The Benchmark summary (Figure 3) shows pretty consistent Windows File Copy performance for RAID 0, 5 and 10 modes. RAID 0 write shows the highest results at 106 MB/s, with 97 and 98 MB/s for RAID 5 and 10, respectively. File Copy read is even more consistent at 93, 91 and 95 MB/s for RAID 0, 5 and 10, respectively.
Figure 3: Thecus N5550 Benchmark Summary
NASPT File copy results are higher than their Windows File Copy counterparts for write (126, 119, 117 MB/s) , but lower for read (88, 86, 84 MB/s) for RAID 0, 5 and 10m respectively.
iSCSI target write performance to target created on a RAID 5 volume came in at 85 MB/s, with read lower at a still-respectable 80 MB/s.
Thecus' USB / eSATA Schedule Backup module was used to run backup tests with our new higher-performance Startech USB 3.0 eSATA to SATA Hard Drive Docking Station (SATDOCKU3SEF) containing a WD Velociraptor WD3000HLFS 300 GB drive.
Since Thecus doesn't provide a way to format external drives, we were only able to test only FAT and NTFS backup formats. Best backup throughput of 45 MB/s was obtained with FAT format and USB 3.0 connection. NTFS backup shared the slowest throughput of 22 MB/s in all three connections (USB, USB 3.0 and eSATA).
Rsync backup to the NAS Testbed running DeltaCopy acting as an rsync target came in at 37 MB/s.
For a competitive look, I ran RAID 5 File Copy charts filtered for dual-core Atom processors. Note that RAID 5 (and 10) tests are run with four drives so as not to give an unfair advantage/disadvantage to NASes with more than four bays.
As we have seen previously, the latest-generation dual-core Atoms (D2700, D2550) don't seem to provide a significant performance boost over previous generation D525 Atoms. The write comparison in Figure 4 shows the N5550 having comparable performance to the D525 1.8 GHz Atom-based QNAP TS-459 Pro +. The other similarly-performing NASes (Synology DS2411+ and Thecus N4800) use the dual-core 1.8 GHz D525 Atom and dual-core 2.13 GHz D2700 Atom, respectively.
Figure 4: Thecus N5550 RAID 5 File Copy Write Comparison
RAID 5 File Copy Read falls just a bit, with the N5550 as much as 10% lower than some other dual-core Atom NASes, but still turning in respectable numbers.
Figure 5: Thecus N5550 RAID 5 File Copy Read Comparison
Conclusion
The Thecus N5550 is one of the most economical five-bay dual-core Atom-based NASes out there, for as low as $550 from reputable etailers. For that price, you'll be able to copy large files to and from it just about as fast as a Gigabit Ethernet connection will allow.
The N5550 is even cheaper than its four-bay N4800 sibling, although it doesn't have the N4800's built-in battery backup. But depending on your needs, you might find a live spare for your RAID 5 array a more useful feature.