As a UNIX veteran who has a vague recollection of /dev/drum, I keep thinking that it would be really nice to have a device to swap to that's somewhere between disk and memory in terms of speed and cost (total installed cost, not just each module).
Mostly, I feel
constrained by the 32-48GB limits on moderately priced ($1-3k) servers.
To go higher, for even modest processor speeds, is a $5-$10k premium.
Moreover, DRAM doesn't really wear out, and it would be nice to put
older, lower density modules to use.
The trouble is, what I've
found so far is either very low capacity, priced much higher than the
memory modules themselves, or both. I'm not particularly interested in
adding 4GB of fast swap to a 48GB machine, though ACARD has something
for $250 with a 48GB limit, with high density modules, defeating my
second purpose. Similarly, I'm not interested in paying $10k for 16GB of
RAM SSD ($625/GB?!) when I could just dump that money into the base
server and get much faster access.
I'm not a hardware guy (in
the EE sense), so I'm genuinely curious about this. Is it really that
difficult/expensive to stick a memory controller (northbridge?) onto a
SATA interface? Am I being too cynical in assuming that it's mere market
"segmentation" without a low-end consumer segment?
described already exists with the name "motherboard," but the software
package "scst" seems woefully incomplete. For example, the MPT-Fusion
driver is still described as "alpha" or early development, so I'm not
holding my breath on reliability, let alone performance. I'm sure
participation by the vendors would help. LSI, are you listening?