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Magnetic recording breakthrough reported

sciencedaily.com

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Re: Magnetic recording breakthrough reported

#11

Post by replax »

jergason wrote: post #3

Can someone smarter at physics than I am explain how this works? The article specifically suggests use in hard drives, but how soon could this realistically be used in commercial hard drives?

In response to your question on availability in commercial HDs, I think that unless a comparable significant advance is made in read speeds, I doubt that you will find it in consumer grade HDDs soon. A disk that can read at e.g. 100mb/s and write at 50gb/s would be not easy to sell to the consumer at a premium price (where do I get data faster than my HD/SSD read speeds from to store?).

I assume though, that it might be used in e.g. CERN, where they need to store a ridiculous amount of data in very short time. Or similar activities where the write speeds are the limiting factor.

Re: Magnetic recording breakthrough reported

#13

Post by arjn »

leeoniya wrote: post #12

my question being, wouldn't these drives be much more susceptible to rapid and massive data loss from changes in ambient or operating temperature?

not any more than regular HDDs. The method described will probably be applied to existing HDD platter technology (my opinon)

Re: Magnetic recording breakthrough reported

#14

Post by InclinedPlane »

ajays wrote: post #10

Terabytes per second? Really?? Given that SATA-3 is still at 6Gbps, this would be 1300x faster than SATA-3. How would you get data to a drive that fast for it to write?

Sort of a moot point regardless. If you have a spinning disk the average latency and maximum read or write speed is determined by the speed of the disk.

Re: Magnetic recording breakthrough reported

#16

Post by toomuchtodo »

replax wrote: post #11
jergason wrote: post #3

Can someone smarter at physics than I am explain how this works? The article specifically suggests use in hard drives, but how soon could this realistically be used in commercial hard drives?

In response to your question on availability in commercial HDs, I think that unless a comparable significant advance is made in read speeds, I doubt that you will find it in consumer grade HDDs soon. A disk that can read at e.g. 100mb/s and write at 50gb/s would be not easy to sell to the consumer at a premium price (where do I get data faster than my HD/SSD read speeds from to store?). I assume though, that it might…

When I was at FNAL on the USCMS data team, we were able to take data from the LHC at ~40Gbps over an optical link and write it out just fine to spinning disk (which would hold it until we could shove it out onto thousands of LTO4 tapes).

I don't think there are going to be a ton of applications for this hardware, but it'll be great for those edge cases where you absolutely need that sort of data rate.

Re: Magnetic recording breakthrough reported

#17

Post by dmoy »

sliverstorm wrote: post #8
rsanchez1 wrote: post #5

How would the performance compare to a SSD?

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?

Re: Magnetic recording breakthrough reported

#18

Post by redthrowaway »

replax wrote: post #9
rsanchez1 wrote: post #5

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 magnet…

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.

Re: Magnetic recording breakthrough reported

#19

Post by ars »

InclinedPlane wrote: post #14
ajays wrote: post #10

Terabytes per second? Really?? Given that SATA-3 is still at 6Gbps, this would be 1300x faster than SATA-3. How would you get data to a drive that fast for it to write?

Sort of a moot point regardless. If you have a spinning disk the average latency and maximum read or write speed is determined by the speed of the disk.

Not necessarily. For example you could have many read heads and read from the disk much faster by reading in parallel. It's complicated to do, but it is possible.

You can also increase the areal density, which means more bits fly past the head per second, which also increases speed, even though you can't increase the rotational or seek speed.

Re: Magnetic recording breakthrough reported

#20

Post by johapers »

afhof wrote: post #6

Does this affect read speed at all? The article only mentions write speed.

The readout will still be carried out by a magnetoresistive sensor, so that is not directly affected. With a smaller bit size it might be necessary to further develop the read head, but the road map for that is quite well understood at the moment.
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