Samsung’s Marketing guys probably pulled a marketing stunt of the year, with a Youtube video which probably cost them less than any of those fancy ads in papers. Guys’n’girls took 24 Samsung 220/200MB Read/Write SSD drives, put’em on an RAID controller and tested them using a Skulltrail system. While achieved speed of 2GB/s was awesome, it also struck me as a pretty low figure for a 24 drive setup. Each drive achieved only 85MB/s, far cry from what those drives are capable of.
Given that a RAID0 array with five Intel or OCZ SSDs gives out 1GB/s, why did Samsung need 19 more drives to only double the speed? 24 drives should achieve 5.2 GB/s read and 4.8GB/s write speed. The problem lies within our current PC architecture. The authors used two PCI Express x4 controllers that cannot give out more bandwidth than 2GB/s read and 2GB/s write – thus, from eight drives onwards, the speed of each individual drive only decreased, from 220MB/s to a lowly 85MB/s.
Secondly, using Skulltrail for seeking maximum bandwidth was never a good idea. Intel Core i7 or AMD’s Phenom II would do much better, without the limitations of archaic FSB architecture.
If Samsung had access to PCIe Gen2 x16 controller (not certain that anyone makes it), then those 24 drives would run at its peak speed, 5.2/4.8 GB/s in R/W operations. This is not to say that the video wasn’t awesome, but bear in mind that those drives could perform way better once that the RAID controller industry catches up. On the other note, I managed to max out Intel’s ICH10R controller – it took six Raptors (no SSDs for me), but the top bandwidth figure out was 450 MB/s, roughly identical to limit which Nova found in his 4-drive SSD test a while ago. If we would put these Samsung hard drives onto ICH10R, you would only need two drives to max it out.
One thing is certain: for SSD technology, PCI Express Gen3 and SATA 3.0 can’t come soon enough.
P.S. Video was awesome guys, now, do the same thing on i7 just for kicks – see the difference in bandwidth between 5.5GB/s Skulltrail and 38.4 GB/s on i7 platform (DDR3-1600).
UPDATE – March 10, 2009 15:10 CET – I have received reports that the story is not appearing on the homepage – seems like an odd thing to happen, but this isn’t the first story that experienced “disappearing act” on this blog. One reason more for going with Custom CMS for upcoming site, BSN*. I apologise for any inconvienience this might have caused, but have no control over it.