Vertex LE vs Crucial C300

[GullLars]

Gullars,
the only thing that comes in between what u say and reality, is that as an idea, this all seem very nice (though it's hard seeing how a dual SF-1200 SSD with a ROC added to it and redesigned PCB, enclosure etc. will only cost 1.5 times a single SF based SSD) on paper, yet ususally, it's harder to implement and not always gets out "linearly"..
though the idea, is indeed interesting.

another thing which comes up, reading your post, is that the compression is (as far as i understand..), what gives u the 2x times speed, yet actually, you don't get the drive to perform at 270MBps (saturating the protocol)..
the drive itself is manipulating data faster then a normal non-compress-using drive, though the badwidth sup[plied by the SF controller, is not 400MBps full duplex, but rather sending ~200MBps to the CPU and ~400MBps (by your calculation) to the NAND flash chips.

i'm yet to have/see the full view/understanding on that drive so i might be missing here something,
yet from a brief overview, so it seems.

the OWC 50GB SF-1500 based drive costs ~230$, take off the 1500 and place a 1200 on it, take top 40-50$ off,
u got a 190$ drive, double by 2 and add (you said 100$ ROC), so you end up with ~450 (+50 for any overhead),
~500$ for a 100GB drive.., let's say 550.

that's not too bad if it would work as u say (double the ability of a LE 100GB and for a reasonable price add up).

To the performance issue, the SSD can handle the RAW speed internally to and from the flash chips. Externally it can saturate the SATA interface if the compression is higher than {interface speed}/{raw speed}, wich is about 1,4x compression for reads, and 2-2,25x for writes. Meaning anything compressed by 1,4x or more will saturate the interface when read, and anything compressable by 2,25x or more will saturate the interface when writing. F.ex. Windows 7 and the MS office 2007 suite is compressable by more than 2x.


When it comes to price of an internally 2R0 (2x RAID-0) SF-1200 drive, could make it as a 3,5" drive, with 2x 2,5" PCBs + one PCB for the ROC with 1x SATA/SAS 6Gbps connection externally and 2x SATA 3Gbps internal connectors to the 2,5" PCBs. So you pay for 2x 50GB SF-1200 + $100 for the 2port ROC only able to handle RAID-0 (not using cache) and the extra PCB it's on. I'll take your word for the OWC 50GB SF-1500 based drive costing ~230$. SF-1200 placed on a PCB whitout the supercap slot could also reduce the cost, but probably not by $50, let's say $25 to $200 pr SF-1200 on the 2,5" PCB whitout the 2,5" enclosure and cables and other stuff.
2x $200 + $100 = ca $500 for 100GB. $500/$380 (agility 2 100GB) = 1,3.
380*1,5 = $570.


*drifting off in idealistic dreams*
It would be nice if SandForce decided to make a PCIe SSD with the same sort of design for prosumers, but then take full use of the NAND for the RAW speed and not limit it to 200-220/120-130 on the larger capacities. By bumping the power in the controller to simelar levles of higher end RAID cards for the higher capacities, you could get several GB/s from a 200GB card for compressible data. Postulating linear scaling of raw performance from the 50GB, raw performance could be 800MB/s read (if 200 raw read is indeed limited by the physical max read of the NAND for the 50GB..),and 500MB/s write, and then be multiplied by compression when possible up to saturation of the PCIe interface. By not artificially write-limiting small block random, IOPS scaling could also be linear from the SATA drives using sandforce's architecture, making it capable of 4KB random write equal to the raw write rate of 500MB/s = 125K IOPS.
SandForce's architecture is actually more suitable for SSD RAID than SSD controllers.
It could also be nice if SandForce made a RAID controller dedicated for flash SSDs (or NAND Flash DIMMs?) taking compression one level higher and sequential steaming of random writes to the HBA. In that case with a powerfull processor you could be bandwidth limited by the PCIe interface for well compressible/compressed data, whitout the SSDs ever knowing the difference, working at their own pace with only (or mainly) sequential writes and both sequential and random reads.

sigh
so many floating thoughts, so little hope of it becoming reality.