To test the performance of the NS4600 we installed four identical 500GB hard disk drives into it (Western Digital Caviar Black WD5001AALS, 7200rpm, 32MB buffer, SATA II). We used Intel NASPT 1.7.0, a popular NAS testing tool.
The NAS was connected to a PC via a Gigabit Ethernet switch. Jumbo Frames technology was enabled on every device. The NS4600 allowed to set a frame size up to 16000 bytes whereas the PC’s network card only supported 9000-byte frames. The PC was configured like follows: an Intel Core 2 Duo 1.8GHz, 4GB of system memory, a Gigabit Ethernet controller, 32-bit Microsoft Windows Vista.
The NAS’s parameters were left at their defaults. Particularly, we turned off all of its extra modules and services. In reality, the file indexing by the media server and the P2P client can affect its performance greatly but our goal was to check out the maximum performance the NAS could deliver. Therefore we turned them off.
The first figure shows the performance of RAID0 arrays made out of different numbers of disks. This array type is not fault-tolerant.
The overall picture is normal except that the single disk is too slow when reading two large files. The situation improves as soon as we add a second disk, though. In this case, the sequential speed is 45MBps and higher, up to a maximum of 56MBps. The speed is lower in comparison with NASes based on faster x86 processors (Atom, Celeron, Core Duo) but they are much more expensive. However, the SmartStor NS4600 with its 600MHz x86 processor is quite competitive to NASes based on ARM and PowerPC processors with clock rates of 1GHz and higher.
As for fault-tolerant arrays, the RAID1 is very good. It is faster than the single HDD at reading and not slower than it at writing. The read speed of the RAID5 array is high at over 40MBps but this array has problems with writing: the 4-disk RAID5 has a write speed of only 20MBps and is even slower than the 3-disk RAID5 (which should have had a lower speed). The RAID10, a rather rare array type for NASes, delivers high performance in every test, notching a top speed of 50MBps.
The test results suggest that the NS4600 has adequate performance for its class, except for fault-tolerant RAID5 which is slower than expected. Hopefully, this will be corrected in the next version of the firmware. So far, you can use RAID10 mode which is almost no different from RAID5 in terms of reliability in this case.