I ran the MSS through our standard testing procedure and found the MSS' performance to be quite good. Figures 26 and 27 are composite read and write throughput vs. filesize plots for the two benchmark tests we ran. These were generated using the NAS Chart Compare Benchmarks feature. Remember that the MSS doesn't support RAID and it doesn't support jumbo frames. So the only benchmarks ran were with 100 and 1000 Mbps LAN connections.
Figure 26: Write performance comparison
The plots show that you definitely want to run the MSS with a gigabit connection since a 100 Mbps LAN will significantly limit its performance. The MSS has the typical drop in performance with increasing filesize seen with most NASes
Figure 27: Read performance comparison
Fans of small filesizes will find that the MSS ranks at the top of the NAS Charts for all four benchmarks run. The MSS' 512MB of memory certainly contributes to this, but there are probably other optimizations at work in the WHS OS, too.
I also used the NAS Charts to compare a few four drive NASes from the top of the 1000 Mbps charts: the Synology CS407, Thecus N5200 and Buffalo Terastation Pro II. Figure 28 shows that the MSS dominates the group in write performance, with the Thecus N5200 coming in second. Even though it's about a year old now, the N5200's performance continues to hold up well against newer designs.
Figure 28: Write performance competitive comparison - 1000 Mbps LAN
The MSS' read performance isn't as clearly superior. It's the best for 32, 64 and 128 MB filesizes, but runs neck-and-neck with the Buffalo TeraStation Pro II for larger filesizes.
Figure 29: Read performance competitive comparison - 1000 Mbps LAN
You can also generate your own charts to look at other modes and compare products.