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How would the performance compare to a SSD?



Well the article mentions that:

"This revolutionary method allows the recording of Terabytes (thousands of Gigabytes) of information per second"

Therefore, If you can write 1TB/sec the seek it would pretty much outperform any SSD cluster, in terms of writespeed. unfortunately, nothing is said about read speeds/access times and I assume that that will be a harder problem. Because they are still storing the data magnetically and the platters don't emit heat based on their polarisation, they still have to pretty much read like normal hdds do. You cannot (until now, like it was not possible to alter the magnetic polarisation of metals other than with another magnetic field) sense the polarisation except for with another magnetic field.

I am really interested in how that will turn out, but before they make a significant advance in read speeds I doubt that the technology will make it into consumer grade HDD's any time soon.


SSD read/write speed is pretty much limited by cost and bus speeds, not technology, as for the foreseeable future you can boost it by putting more chips in parallel (which is why current high end SSD solutions are pretty much all on PCIe cards, because they're already way too fast for SAS or SATA etc.). The same would probably become the limiting factor for this technology too, even if they can solve the read speed issue.


On top of the read problem, they have to deal with the fact that HDDs are just really energy-inefficient. With the world going to mobile, we can't predicate the future on the need for moving parts.

It's a damned cool technology, and I hope it leads to something useful, but I just can't see it becoming the prevalent paradigm.


Yes, you're right the world is going mobile and in mobile less (no) moving parts is better (more durable etc.) That is also why I think that consumer grade devices will be unlikely (unless read speeds are bumped up, too)

But mobile, in our case, means also a shift to the cloud, where significant more potent storage technologies could make a real difference. I really hope, too, that technology will lead to something new.


Fair enough. It's hard to see where these kinds of write (but normal read) speeds would be necessary, even in a server farm, but I guess the beauty of enabling technologies is that they allow for use cases no one could have imagined when they were conceived.


Shooting from the hip here; I expect seek disparity would remain about the same, while maximum bandwidth would skyrocket.

Actually, hold on, I wonder if seek would improve very noticeably? Is seek time mostly the long-distance movements of the head, or the locating of the file in-track after the head has traveled? If it is the latter, you might be able to boost seek quite a lot.


"Seek time" as you are putting it is almost all the lateral movement of the read head (not the rotation).

Though what you're really going for here is "access time", which is "seek time" (properly defined as just the lateral movement of the head) + "rotation time" (what you call "locating of the file", which is actually just sitting there waiting for your 7,2k rpm to come around once every 4ms or so - rotating disks rotate at a constant rate, you can just do the math). A Western Digital Caviar Blue (random benchmark, I only know this because it was the last drive I bought) has a ~9ms seek time.

To recap:

Access time = seek time + rotation time ( + negligible other times, well under 10~100us)

Rotation time ~4ms (3ms for 10krpm) Seek time ~9ms (supposedly ~4 for really high end drives)

Now this is just with the technology we have right now. I do not know enough about the constraints on hardware to know if they could push the limits. For instance, if the actual write (/read?) bandwidth could theoretically be higher, would it be possible to just rotate the disk faster and/or bump up the head seek time?




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