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HAMR Hard Disk Drives Postponed To 2018 (anandtech.com)
An anonymous reader writes: Unfortunately the hard disk drive industry is not ready to go live with Heat-assisted Magnetic Recording (HAMR). The technology is yet not reliable enough for mass production. Over the years, producers of hard drives, platters and recording heads have revealed various possible timeframes for commercial availability of drives with HAMR technology. Their predictions were not accurate. The current goalpost is set to year 2018. While solid state disks based on Flash memory keep seeing rapid improvements as well, HDDs still kick butt in scenarios where high areal density is more important than ripping transfer speeds. The areal density of HAMR products is predicted to exceed 1.5 Tb per square inch.
thats a lot porn per square inch :P
Oh wait ... not yet
The summary lists HDDs as viable vs SSDs when "high areal density is more important than ripping transfer speeds" but in most applications it's the random access time that's more useful and SSDs are better than HDDs in this regard by several orders of magnitude.
Of course it's not reliable, who the hell thought that using a HAMR on hard drives was a good thing? That's what I use to destroy hard drives!
Dear Dice Editors:
If you are going to post a summary which says what *might* be possible in the future, it's helpful to know what the current state-of-the-art is. For example, if you are going to have a summary that says the areal density of HAMR products is predicted to exceed 1.5 Tb per square inch it would be nice to know that Seagate is already shipping a drive with 1.34Tb/in^2 according to Wikipedia.
As it turns out, context matters when giving statistics, or there is no reference to know if the statistic means anything. Given what I found in 30 seconds of using Google, that would mean that HAMR is expected to yield ~12% increase in density from the current state-of-the-art.
You're welcome.
Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.
Not in all cases, or even many. What do I care if the access time is 0.5 seconds longer for my 20+TB file of my research data? I would rather have it sit on one to two drives ( with backups OFC ) rather than spread across 20+ SSD drives, which, just by the number needed alone are more prone to failure.
In this case transfer speed isn't an issue either, as long as it isn't significantly slower than current HDD tech, since no matter what, data analysis is going to take quite a bit of time and it wouldn't really matter if it took 12 hours instead of 8 to transfer.
In other words, SSD VS. HAMR are made for entirely different use cases. You won't be needing the data density of HAMR for an OS drive ( well maybe you will with the bloat that everyone is putting into OS installs, I mean seriously 5-10GB just for the bare bones OS on Linux, Windows and Mac...) but the density would be useful in places that store and use extremely large data sets.
To err is human; effective mayhem requires the root password!
Actually, if you do more than gaming, there are MANY situations where capacity is far more important than blistering performance.
For example, on one of my home NAS boxes, as long as performance is adequate to stream 1080p video to my STBs, faster drives offer little to no additional value. Therefore the price/performance of spinning disk is FAR more attractive than SSD. I won't even go into all of the situations in my professional life where wasting money on extreme performance would be flat out irresponsible.
SSDs definitely have their place, but spinning disk is going to remain important for quite some time yet.
Not in all cases, or even many. What do I care if the access time is 0.5 seconds longer for my 20+TB file of my research data?
You may not need instant access to that much data. But then again, if your 1/2/sec longer is multiplied thousands of times a day, five days a week, 4.25 weeks a month ... That is almost 3 hours each month of wasted time, and almost a full week a year of wasted time. My guess, is that you're actually not waiting 1/2 second per, times 1000 a day, it is more likely that you're wasting 3-5 seconds per, several thousand times a day, but since you aren't measuring, you will never know.
However, based on my Anecdotal evidence (personal experience), there is even a greater cost to your short sightedness that you may be ignoring (or ignorant of). Speed is more than just time, sometimes the difference between whether or not you actually do something. And not doing something, because it takes a long long time, is lost opportunity, and opportunities lost can never be recaptured.
And until you actually experience the speed difference, you're not really able to appreciate what it really means. Booting in 10 seconds vs 2 minutes might not seem impressive, until you actually see it.
Agent K: A *person* is smart. People are dumb, stupid, panicky animals, and you know it.
Areal density doesn't mean shit. Volumetric density is what counts.
It will come with hurd pre-installed.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion. -- Spazmania (174582)
Yeah, because I want to pay for hundreds of terabytes of SSD for nearline archival storage.
Nope. Spinning rust, please and thank you!
Slashdot still doesnâ(TM)t support Unicode after it was added to the HTML standard in 1997.
As another commenter pointed out, the 1.5Tbit/in^2 number in the posting (which is taken from the original article) is pretty bogus. Seagate's 2TB 7mm 2.5" drive has an areal density of 1.32Tbit/in^2, and it's probably a safe bet that they (and WD) can wring another 15% density improvement out of SMR technology in the next year or two.
For those commenters bemoaning the fact that the highest density drives today are SMR rather than "regular" drives, get over it - the odds of conventional non-HAMR, non-shingled drives getting much denser than the roughly 1TByte per 3.5" platter we see today are slim to none:
To get smaller bits, you need a smaller write head. That smaller write head has a weaker magnetic field. The weaker field means the media has to be more easily magnetizable (i.e. has lower coercivity). The lower coercivity media needs to have a bigger grain size (size of the individual magnetic domains), so that grains don't flip polarity too often due to thermal noise.
Since a bit can't be smaller than a grain, that means that smaller your write head is, the larger your minimum bit size is. Eventually those two lines cross on the graph, and it's game over.
Two ways of getting out of this are SMR (shingled magnetic recording) and HAMR (heat-assisted magnetic recording):
SMR - stop making the write head smaller, but keep making the bits smaller. Overlap tracks like clapboards on the side of the house (where'd this "shingle" nonsense come from?), allowing small bits with large write heads. Of course this means that you can't re-write anything without wiping out adjacent tracks, which means you need something like a flash translation layer inside the drive, and because of that, random writes might be *really* slow sometimes. (I've seem peak delays of 4 seconds when we're really trying to make them behave badly)
HAMR - Write your bits on low-coercivity media with a tiny, wimpy head, and store them on high-coercivity media with tiny magnetic grains. How do you do this? By heating heating a high-coercivity media with a laser (say to 450C or so) to reduce its coercivity to reasonable levels, then letting it cool down afterwards. But you need a big laser (20mw?) on each head, which causes a whole bunch of problems. Which is probably why they're delaying them.
Oh, and you can overlap tracks on HAMR drives, creating an SMR HAMR drive, with even higher density but the performance problems of both technologies. Which they'll probably do as soon as HAMR hits the market, because with today's SSDs the market for fast HDDs is dying a very quick death.
I'm kind of surprised that the hard drive industry has not created bigger (i.e. size, not just capacity) drives. It seems that a large portion of hard drives these days are going into huge arrays in data centers. All the data that needs super-quick access times is moving to SSD. The multi-TB near line data is staying with HDD storage. It seems to me that the industry could put out a drive with something like 5 inch platters; 20 platters per drive; a really good motor; redundant heads per platter; and an extra, backup circuit board. They could fill it with Helium and get the cost down to below 1 cent/GB. No one would put one in their desktop, but data centers might really like it.
3½" diskettes were never referred to as a hard disk, like their 5 1/4 counterparts they were referred to as floppies. Named after the internal magnetic medium, not the casing.