On Sun, 11 Jan 2009, Mark Kirkwood wrote:
david@xxxxxxx wrote:
On Sat, 10 Jan 2009, Luke Lonergan wrote:
The new MLC based SSDs have better wear leveling tech and don't suffer the
pauses. Intel X25-M 80 and 160 GB SSDs are both pause-free. See
Anandtech's test results for details.
they don't suffer the pauses, but they still don't have fantasic write
speeds.
David Lang
Intel's SLC SSDs should also be good enough but they're smaller.
From what I can see, SLC SSDs are still quite superior for reliability and
(write) performance. However they are too small and too expensive right now.
Hopefully the various manufacturers are working on improving the size/price
issue for SLC, as well as improving the performance/reliability area for the
MLC products.
the very nature of the technology means that SLC will never be as cheap as
MLC and MLC will never be as reliable as SLC
take a look at
http://www.imation.com/PageFiles/83/SSD-Reliability-Lifetime-White-Paper.pdf
for a good writeup of the technology.
for both technologies, the price will continue to drop, and the
reliability and performance will continue to climb, but I don't see
anything that would improve one without the other (well, I could see MLC
gaining a 50% capacity boost if they can get to 3 bits per cell vs the
current 2, but that would come at the cost of reliability again)
for write performance I don't think there is as much of a difference
between the two technologies. today there is a huge difference in most of
the shipping products, but Intel has now demonstrated that it's mostly due
to the controller chip, so I expect much of that difference to vanish in
the next year or so (as new generations of controller chips ship)
David Lang
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