Breaking News
News & Analysis

Is IBM serious about phase-change memory for servers?

11/3/2010 02:43 PM EDT
26 comments
NO RATINGS
Page 1 / 2 Next >
More Related Links
View Comments: Newest First | Oldest First | Threaded View
Page 1 / 3   >   >>
xprmntl
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
xprmntl   6/6/2011 3:00:11 PM
NO RATINGS
PCMs have 30X or better write times (Samsung claim) than NOR and are low voltage (~2V vs 10V+). @Kris, The memory chip in this case is an industrial prototype, not university-made, thus it has already been tested to meet certain cycling specifications by the manufacturer (though as a prototype part, the study found write performance issues). This was not a test of the PCM, but rather a new PCM _drive architecture_ and _software_ for speed benchmarking. I fail to how extended cycling times will make a test of the architecture any different?

krisi
User Rank
CEO
re: Is IBM serious about phase-change memory for servers?
krisi   6/4/2011 2:44:28 PM
NO RATINGS
To @xprmntl, academic testing is very different than industrial testing...I worked as a prof at 5 universities around the globe in my career and most of my academic colleagues would test one device, make few measurements, write a paper and move on...needless to say in industry you test things thousands if not millions of times, very, very different, Kris

resistion
User Rank
CEO
re: Is IBM serious about phase-change memory for servers?
resistion   6/3/2011 11:22:56 PM
NO RATINGS
Why not use NOR flash then, all these PCMs are positioned as NOR drop-ins.

xprmntl
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
xprmntl   6/3/2011 11:09:39 PM
NO RATINGS
@inewski The academic claims are made from testing actual PCM devices (Micron NP8P128A13B1760E), not just what they think. Scaling could be an issue, so remains to be seen. PCM with a vertical access device would be really nice, though... Memorywranglers link was bad, so try this: http://cseweb.ucsd.edu/users/swanson/papers/HotStorage2011-Onyx.pdf The PCM devices are qualified for 85C, similar to current Flash; 150C is a high temperature, automotive spec.

krisi
User Rank
CEO
re: Is IBM serious about phase-change memory for servers?
krisi   6/3/2011 5:51:32 PM
NO RATINGS
I agree with Peter and would be very skeptical of any academic claims...there is a wide gap between what academics think and what actually works ;-)...I have been on both sides of this divide and have seen this difference of point of views thousands of times...Kris

Peter Clarke
User Rank
Blogger
re: Is IBM serious about phase-change memory for servers?
Peter Clarke   6/3/2011 5:09:54 PM
NO RATINGS
@memorywrangler This is an academic paper from UC San Diego and one of the observations therein is: "These results show that (assuming PCM scaling projections hold) PCM-based storage array architectures will be a competitive alternative to ?ash-based SSDs." But does that assumption hold?

memorywrangler
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
memorywrangler   6/3/2011 4:58:55 PM
NO RATINGS
The original Moneta system used DRAM, but the version described in this article does real PCM -- 10GB of it, in fact. You can read about it in detail here: http://cseweb.ucsd.edu/users/swanson/papers/papers/HotStorage2011-Onyx.pdf

Volatile Memory
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
Volatile Memory   11/8/2010 11:16:38 PM
NO RATINGS
The UCSD Moneta storage array DOES NOT USE ANY actual PCM, apparently. It uses actual DRAM but (fake) performance data for PCM to model the performance of the array. According to that fake input data, their imaginary array achieves 1.5 GBytes/second or so sustained write, which is not impressive, given that Fusion-IO's Duo ACTUAL Flash drive already has achieved the same speed using SLC NAND Flash. http://cseweb.ucsd.edu/~acaulfie/papers/Micro2010_Moneta.pdf Garbage-in, garbage-out, as they say. Oh, and by the way, 64GB worth of PCM costs over $16,000 (compare to just $100 if MLC NAND Flash is used). Good luck with that!

greenpattern
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
greenpattern   11/7/2010 6:07:05 PM
NO RATINGS
Any storage medium must be qualified on retention. The PCM can't survive at 150 C and has the problem of drifting resistance and threshold voltages.

memorywrangler
User Rank
Rookie
re: Is IBM serious about phase-change memory for servers?
memorywrangler   11/7/2010 4:45:04 PM
NO RATINGS
PCM certainly faces some significant technology challenges, but I think IBM is right to see it as a potentially transformative technology, especially for storage. If PCM follows even somewhat optimistic trends in terms of scaling and performance, it will will dramatically speedup storage. A group at UC San Diego recently built a prototype storage array to explore the potential impacts (google "moneta UCSD"). The performance they achieve is impressive.

Page 1 / 3   >   >>
August Cartoon Caption Winner!
August Cartoon Caption Winner!
"All the King's horses and all the KIng's men gave up on Humpty, so they handed the problem off to Engineering."
5 comments
Top Comments of the Week
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Times on Twitter
EE Times Twitter Feed
Flash Poll
Radio
LATEST ARCHIVED BROADCAST
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.