The HMNHD was tested using our new, faster testbed and procedure that includes both Iozone and Vista SP1 file copy benchmarks (the full testing setup and methodology are described on this page). The test unit had the latest 1.029 firmware and was tested with 100 Mbps and 1000 Mbps LAN connections.
I was surprised, no, make that shocked, to see the product at the top of both the 100 and 1000 Mbps Average Write Performance charts! But a look at both the average read performance charts and the Throughput vs. Filesize plots (Figure 7) shows that the write averages are heavily skewed by cached performance that doesn't drop out until the 512 MB file size test.
Figure 7: Throughput vs. filesize summary
This is very unusual, because cached performance usually goes away once test file size exceeds NAS RAM, which is 64 MB for the HMNHD. I don't really have an explanation for this unusual caching. But I ran the iozone tests three times and the behavior was consistent.
The Vista SP1 file copy tests shown in Figures 8 and 9 present a more accurate reflection of the HMNHD's real-life performance.
Figure 8: Vista SP1 file copy write comparison - 1000 Mbps LAN
The write results show that the NAS isn't able to take much advantage of its Gigabit Ethernet LAN port with only 12.7 MB/s average write transfer rate. Figure 9 shows about a 2X improvment for read, however, averaging 27.9 MB/s. There is also about a 10 MB/s advantage over the Marvell-powered Buffalo and Linksys NASes.
Figure 9: Vista SP1 file copy read comparison - 1000 Mbps LAN
For a competitive comparison, I chose the Linksys Media Hub and Buffalo LinkStation Live LS-CHL. Of the two, the Buffalo product is more closely matched for pricing and features, since it also is a single-drive NAS with media-serving capability. But I included the Linksys product too because of its media focus and similar performance.
Figure 10 shows the write comparison with a Gigabit LAN connection. Once you get past staring at the unusually high cached speed as lower file sizes, note the Iomega's slight (~3 MB/s) throughput advantage starting from 1 GB files on up.
Figure 10: Competitive write comparison - 1000 Mbps LAN
The read comparison in Figue 11 shows the HMNHD's clear throughput advantage for all file sizes in the benchmark.
Figure 11: Competitive read comparison - 1000 Mbps LAN
I think that Iomega did a pretty good job with the Home Media Network Hard Drive's feature set and has priced it competitively. Although you can get a Terabyte NAS for a bit cheaper (a WD My Book World or LaCie Network Space for around $165), $180 for the HMNHD's combination of performance and features is pretty good.
But there are four things that I think would make a good product better:
- Include a media import tool: Both the Cisco / Linksys Media Hub and refreshed HP MediaSmart Server include utilities that automatically find still image, music and video files and automatically copy them to the NAS. Given the intended buyer, I think this would be a helpful addition.
- Idle drive spindown: There is no sense in having the drive spin if it is not being used. Even though total power consumption is 12W, lower is better. And buyers are paying attention to NAS power consumption, since they are on constantly.
- Self-contained NAS backup: A big advantage that Buffalo products have is their ability to do scheduled NAS-to-NAS backup (although only to other Buffalo NASes). Even though the bundled Retrospect Express HD can be used to back up the HMNHD shares to other networked shares, it requires a computer to do it. Adding self-contained, scheduled backup to an attached USB drive or network share would be a very useful addition for data security
- Integrate Mozy Home: Having a leading cloud storage service as a sibling company is an advantage that Iomega / EMC should take better advantage of. Mozy Home backup should be built into the NAS so that it can back itself up without depending on a client computer.