Introduction
I have had an MSI Wind PC sitting on my bench for months, waiting for me to explore its suitability as a DIY NAS. But other projects and reviews kept bumping it to the back of the work queue, particularly since I have explored the Intel Atom for DIY NAS use both in Build Your Own Atom-based NAS and Atom vs. Geode: Which Makes a Faster, Cheaper NAS?.
Then about a month ago, VIA sent its C7-D powered ARTiGO A2000 Barebone Storage Server in for a look. So now that I have cleared some of the NAS review backlog and have a new, faster NAS test platform in place, the time has come to see how these two low-cost CPU platforms compare for rolling your own NAS.
MSI Wind PC
At the time (last October), the MSI Wind PC was the only Atom-based barebone system that you could get. Since then, Jetway and Shuttle have both produced small form-factor barebone systems capable of supporting two (and more) SATA drives.
| MSI Wind PC | |
|---|---|
| CPU | Intel Atom 1.6 GHz |
| Motherboard | MSI custom w/ Intel 945GC North Bridge, ICH7 South Bridge |
| RAM | pqi 1 GB DDR2 533 SO-DIMM |
| Data Drives | Hitachi Deskstar HDS721680PLA380 80GB 7200RPM 3.0 Gb/s SATA 8MB |
| Ethernet | Realtek 8111C (on board) |
| OS | Ubuntu Server 8.10 + mdadm + Webmin on 2 GB USB Flash drive |
Table 1: MSI Wind PC Test Configuration
Table 1 summarizes the configuation details of the NAS that I put together using the Wind PC and Figure 1 shows the box. I should note that MSI did not respond to my request for a review unit. So I ended up buying one from NewEgg.
Figure 1: MSI Wind PC
Figure 2 shows the Wind PC’s innards, with the metal cage that holds the drives and front panel ports removed. The board is relatively large, with a single SO-DIMM RAM socket is at the upper right of the photo and the infamous CF slot below it. I say "infamous" because you have to disassemble the entire system to insert the CF card, since it backs up right against the side of the enclosure.
Figure 2: MSI Wind PC, drive assy removed
Figure 3 shows the Wind PC with the drive assembly in place. The cage has two bays that each hold a single drive, one 3.5", the other 5.25". I just secured one of the 3.5" SATA drives with a single screw in the 5.25" inch bay. If you want to mount the drive more securely, you’ll need to invest in an adapter tray or drill a hole for a second mounting screw. The Wind PC comes with SATA power and data cables, pre-cut to reach the 3.5" and 5.25" drive bays, and mounting hardware for the drives.
Figure 3: MSI Wind PC, drive assy installed
I was going to install the OS on a CF drive. But I ended up just putting it on a USB flash drive that I plugged into one of the front ports, instead.
VIA ARTiGO A2000
VIA apparently thinks there is a sizeable DIY NAS market out there and has added a mini server to its ARTiGO Barebone system line. The ARTiGO A2000 Barebone Storage Server is more compact than the MSI Wind PC and has two real 3.5" SATA drive bays, complete with backplane-mounted power and data connectors.
| VIA ARTiGO A2000 Barebone Storage Server | |
|---|---|
| CPU | VIA 1.5GHz C7-D processor |
| Motherboard | VIA custom w/ VIA VX800 Unified Digital Media IGP chipset |
| RAM | Transcend 1 GB DDR2 667 SO-DIMM |
| Data Drives | Hitachi Deskstar HDS721680PLA380 80GB 7200RPM 3.0 Gb/s SATA 8MB |
| Ethernet | VIA VT6130 (on board) |
| OS | Ubuntu Server 8.10 + mdadm + Webmin on 2 GB USB Flash drive |
Table 2: VIA ARTiGO A2000 Test Configuration
Table 2 summarizes the test configuration for the A2000 and Figure 4 is the product "beauty" shot. VIA provided the system for review and included the RAM, which normally does not come with the product. I moved the two Hitachi drives over from the MSI box and a second USB flash drive for the OS.
Figure 4: VIA ARTiGO 2000
Figure 5 shows the inside of the ARTiGO 2000. The drive bays are built right into the main chassis sheet metal. The yellow thing is a BIOS battery that was flapping around the cabinet. It wasn’t clear where it belonged and was probably loose because VIA sent a system that had obviously seen some previous use.
Figure 5: VIA ARTiGO A2000 inside top view
Figure 6 lowers the camera angle so that you can see a bit more of the Nano-ITX main board. The single SO-DIMM socket with RAM installed is to the left of the board. Most of the rest of the board is covered by a heatsink cooled by a small fan (visible). The approx. 3" case fan is attached to the rear chassis wall.
Figure 6: VIA ARTiGO A2000 side view
Figure 7 shows the two systems side by side. The ARTiGO A2000 is obviously designed as a NAS, with no room for a 5.25" drive and small footprint. Both systems were equally quiet in operation, despite the Wind PC’s smaller case fan.
Figure 7: The two systems
Performance Test
Both systems were configured with 1 GB of RAM and had Ubuntu Server 8.10 installed on a 2 GB USB flash drive. I checked only the Samba server option during installation and then added the mdadm Linux RAID utility and Webmin for browser-based admin. See the instructions from the Atom-based NAS article if you need help with the install.
I tested both RAID 0 and RAID 1 configurations, using a recommended 32 KB block size with each, but with only a Gigabit Ethernet LAN connection. I didn’t bother testing at 100 Mbps, since I knew both chipsets could produce better than 12.5 MB/s throughput. I also didn’t test with jumbo frames, mostly because I didn’t want to spend the time figuring out how to set it up via the Ubuntu command line.
I had previously said that I was going to try using Ubuntu Desktop instead of Server, the next time I did a DIY test. But after some quick Googling, I didn’t find any instructions for installing Desktop to a flash drive, then setting up a separate data RAID volume. So, in the interest of time, I went the way that I knew.
I entered the results into the NAS Chart database so you can compare them against other products. But since I used the new NAS test bed and procedure keep in mind that the results aren’t directly comparable to those in Build Your Own Atom-based NAS or Atom vs. Geode: Which Makes a Faster, Cheaper NAS? or most other products in the database.
It turns out, however, I have a good mix of NAS platforms among the products that I have tested with the new testbed. So I was able to generate the informative write comparison plot shown in Figure 8. (Note that all systems were configured in RAID 0 for this plot, except the Cisco/Linksys which was tested in its factory single-drive configuration.)
The systems in this plot are the NETGEAR ReadyNAS Pro (Intel E2160 Dual-Core), Thecus M3800 Stream Box (AMD LX800 Geode), Cisco/Linksys Media Hub (Marvell 88F5182 "Orion" Soc) in addition to the VIA (VIA C7-D) and MSI (Intel 1.6 GHz Atom) boxes.
Figure 8: RAID 0 write performance – 1000 Mbps LAN
Concentrating on file sizes 256 MB and higher to get past cache effects, the ReadyNAS Duo turned in the highest performance, which it should, since it’s the most expensive system represented in this comparison! And it’s no surprise that the Marvell Orion-based Cisco/Linksys turns in the lowest performance, since it is uses a low-cost SoC.
But the interesting comparison is among the C7, Atom and Geode. The Atom-based MSI Wind PC comes in slightly faster than the VIA C7-based ARTiGO, although both have speeds in the 35 to 40 MB/s range. But both edge out the Geode-based Thecus, which stays below 30 MB/s.
The read story shown in Figure 9 is a bit tougher to sort out among the Geode, Atom and C7. The MSI and VIA boxes again sort of track each other including a significant drop in speed once they hit their 1 GB RAM size. But the Geode-based Thecus M3800’s throughput stays nice and steady at 50+ MB/s from filesizes of 256 MB on up. I suspect that this could be due to OS and other tuning in the M3800, since it is running an entirely different OS configuration, but that’s just a guess.
Figure 9: RAID 0 read performance – 1000 Mbps LAN
Moving on to the RAID 1 write comparison (Figure 10), the NETGEAR and Thecus products drop out since I ran RAID 5, not RAID 1 tests on them. Both the VIA and MSI NASes chug along in the 30 MB/s range, while the Cisco/Linksys can only manage in the low teens.
Figure 10: RAID 1 write performance – 1000 Mbps LAN
The RAID 1 read plot (Figure 11) shows a similar story, with the VIA and MSI systems clearly beating out the Cisco/Linksys. Once again, however, throughput on both really takes a hit once the Gigabyte of RAM in the VIA and MSI systems is exceeded.
Figure 11: RAID 1 read performance – 1000 Mbps LAN
Performance Test – Vista SP1 File copy
My new test suite includes filecopy tests between the Vista SP1-based NAS testbed system and the NAS under test and Figure 12 holds the results for RAID 0 write. This comparison includes a second single-drive Marvell Orion-based system (the Buffalo LinkStation Live LS-CHL) because I had the data. But it also shows the similarity in performance between two Orion-based NASes.
As expected, the ReadyNAS Pro is the clear performance winner. But the Atom-based MSI Wind PC isn’t too shabby, coming in at 56 MB/s.
Figure 12: Filecopy JBOD, RAID 0 write performance – 1000 Mbps LAN
The read comparison in Figure 13 has similar results and rankings, except for the Thecus M3800. I first thought it was a data entry error, so went back and rechecked my tests. But for both RAID 0 and RAID 5, both with and without jumbo frames, read performance with a Gigabit LAN connection is consistently 2X write speed for the M3800!
Figure 13: Filecopy JBOD, RAID 0 read performance – 1000 Mbps LAN
Closing Thoughts
I don’t think I’m going to declare a clear winner here between the VIA C7 and Intel Atom. It looks that they are pretty evenly matched for performance and generally in the same class as the Geode LX800.
Keep in mind, however, that the performance of a DIY NAS can vary greatly with the choice of operating system, RAID block sizes and other tunings that can be performed, especially with open source distros. I made no attempt to squeeze the most performance out of any of these products tested and your results could be better…or worse.
That said, the MSI Wind PC is clearly a more cost effective way to build a two-drive NAS capable of producing write and read speeds in the 30 – 40 MB/s range than the ARTiGO A2000. As I write this, you can pick one up for around $140, while the going rate for the A2000 is $299. I think that for the extra $150 or so, I can live with having to kludge in the second drive.
The other thing I have gleaned from this exercise (and my testing of many, many other NASes) is a general feel for what different CPU platforms can produce for NAS performance. So at the risk of making gross generalizations that will be quickly proved wrong by readers much smarter than I, here are my broad rules of thumb for classifying NASes based on the different processor families compared:
- Marvell Orion based NASes will generally produce throughput in the mid-to-high teen MB/s
- NASes using the VIA C7, Intel Atom or AMD Geode will provide read/write performance in the 30 – 40 MB/s range
- When you move up to NASes based on Intel Celeron or Dual-Core or Freescale MPC854XE, you can see speeds of at least 50 MB/s and more like 70 MB/s.
The above speeds are those obtained with iozone testing and exclude caching effects on both the NAS and client system. File copy speeds, which do include cache effects and a mix of small and large file sizes, especially using Vista SP1 on the client side, can be much higher, as shown by the 100 MB/s results obtained with the NETGEAR ReadyNAS Pro.
So if you’re looking for a low-cost way to build a dual-drive NAS, you can choose a motherboard using an Intel Atom, VIA C7 or AMD Geode CPU and be pretty certain of getting better than 2X the performance you can get from any (current) off-the-shelf NAS.