Slashdot Mirror
Seagate Releases Hybrid Hard Drive
An anonymous reader writes to tell us Seagate has released a new hybrid hard drive. This new drive adds the speed of a solid state drive to the conventional hard drive. Originally designed for laptops this new drive comes in 80, 120, and 160 GB flavors and features 256MB of flash memory.
Didn't samsung or some such outfit already do this?
I've seen one of these at a trade event in Atlanta earlier this year. The idea is great, and after much strenuous testing, seemed to still work great. I can't wait to get my hands one some!
"Snatching defeat from the mouth of victory on a daily basis."
However, why did they only include 256MB of flash storage instead of a larger quantity like 2 GB or so?
Many people who exercise smaller flash storage options get flash drives larger than 512MB, so was it really that much more expensive to bump up the available flash storage a little bit?
Regardless, I look forward to the performance benefits devices like these will provide.
Have 'they' solved the problem of the limited number of writes a flash device device can handle. If it's only going to last a few months and then wear out I won't consider it! Pity the poor fool that forgets to turn off atime updates.
Lurking at the bottom of the gravity well, getting old
http://www.pcworld.com/zoom?id=138102&page=1&type=table&zoomIdx=2 -attached to- http://www.pcworld.com/article/id,138102-c,harddrives/article.html
Both hybrids, Samsung AND Seagate were not only more expensive, they were considerably slower in tests vs. a traditional harddrive. I understand the drive to be green, but I think I'm going to wait a few years before jumping on this bandwagon!
Good. These are required in order to run Vista. Or wait...
this?
I have excellent Karma and I am not afraid to Troll it.
But with USB 2.0, still potentially faster than a bare HDD, right?
My blog
Can't read the article but this will help understand about the Hybrid drives.
Since laptops can't support the faster speeds that their desktop brethren, any access time improvement is desirable. You can keep your most frequently used data on the Flash or as a buffer, such as during a movie. Another benefit is that flash takes less energy to read than a HDD.
Here's also a review of the drive itself
import system.cool.Sig;
Windows has this thing to let the drive go to sleep when you're not using it... ...except it never does because Windows is always syncing it or doing something. It never gets enough idle time to actually spin down.
If these drives could fool Windows into letting them go to sleep we might be onto something.
No sig today...
For Hybrid Hard Drives to live up to promises. After a bit more digging - There is still a lack of results from this drive, although boot time and power savings are starting to show up. RAM caches have been around for years, and getting even 1 GB of flash memory is getting down to pretty reasonable levels. Why is this commanding a 30% premium and delivering unspectacular benefits? Unless there's a solid standard behind addressing for HHD's exists, there's no point in blaming BIOS or Vista for a problem that could also be addressed in on-drive logic.
Meh.
http://www.seagate.com/ has a press release on their home page.
Integration can solve a key point which is data integrity during an abrupt power event.
(see above).
AIK
It's ironic that hybrid cars save energy by spinning a platter and hybrid hard drives save energy by not spinning a platter. It's like blowing on your coffee to cool it and blowing on your hands on a brisk day to warm them. If we could just hook these devices up in round-robin, we'd have a perpetual energy machine!
I read an article somewhere that showed how a flash based drive could outlast a platter drive by efficient use of an algorithm that rotated through the bits. I don't recall any further information on this though, such as performance impact. Sorry for the lack of a link. I am sure you can google it though. :)
I do not respond to cowards. Especially anonymous ones.
This is about having longer laptop battery life. These days, processors are pretty good at throttling back. So the next big consumers are the harddrive and the screen (or rather its backlight). Well, hybrid harddrives offer a potential solution. Cache frequently needed data and small writes to flash, and you can spin up the drive platters less often. That saves power which increases the time you get on battery. Also it actually will make a laptop MORE responsive in that if the disk is spun down, the flash can handle things as it spins up so everything doesn't have to come to a halt waiting for it.
I don't know how much of a use these will be in desktops, but in laptops it seems like a really good idea. Also, Seagate drives normally perform slower than the competition. In basically all the tests I've seen, their drives are on the bottom. Of course we are talking a difference of a few percent at most, and perhaps that's also the reason their drives last longer. Maybe they don't push them so hard.
Around 1956, electronics makers began selling hybrid radios with both vacuum tubes and transistors. Emerson's vest-pocket portable model 843 used tubes in the rf stages and a pair of plug-in transistors for audio output. A 6 volt battery lit up the tubes and transistors, while a 67 volt battery kept the tubes' electrons jumping from cathodes to plates.
From Emerson's adverts: "Transistors are so tiny they must be seen to be believed. Transistors are so sturdy they won't break... They will last for life!" and give "greater power without distortion - full reproduction of voice and instruments, balanced tone quality, and greater power output with less distortion, not to mention low battery drain"
What other mixed hybrids have came along? Was there ever a hybrid horse and car?
Does that mean that the drives will not work with Linux?
What is ReadyDrive:
http://www.microsoft.com/windows/products/windowsvista/features/details/performance.mspx
I'm summarizing what I learned from the German c't computer magazine, which has tested the various new technologies like ReadyDrive and others in Vista and also tested Flashdrives and Flash memory in general. Read the current issue of this magazine for in-depth analysis.
1) Pure Flash disks have only ONE advantage over harddisks: they are less sensitive to mechanical stress. In real-life scenarios, they don't safe power, and they are most definitely not faster than 2.5 inch drives. They ARE faster than 1.8 inch ones often used in ultra-mobile PCs, so there they indeed provide a benefit. For everyone else: especially write performance sucks compared to modern 2.5 inch disks, and read performance is at most en par. True, they don't need to position any heads so random access should save time - but according to the real-world tests made by c't that benefit isn't noticeable.
2) c't testers were very suspicious about how long Flash memory could survive as HD replacement where writing happens all the time, and yes, Flash cells have a limited lifetime, one cannot write too often. That's the theory. In practice c't testers were unable to make even the cheapest Flash USB stick show any sign of memory loss even after something like 16 million write cycles, when they gave up further testing because that's many many years of real-work usage. (pg. 104 of c't 21/2007)
3) Intel TurboMemory or MS Vista SuperFetch, ReadyBoost or ReadyDrive were shown to provide no measurable benefit AT ALL.
Suspicion of Hitachi and others seems to be that the current implementation in Vista isn't quite finished and SP1 should provide an update, and second the amount of Flash memory is waaaaaay too small.
Original article (German): http://www.heise.de/ct/07/21/100/
With a famous quote, "By the second generation products will see the system benefits", by Melissa Johnson, a product manager at Seagate. http://www.extremetech.com/article2/0,1558,2188425,00.asp?kc=ETRSS02129TX1K0000532 http://www.dailytech.com/article.aspx?newsid=9195
We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
Why does any of this require OS hooks? If you're going to have OS hooks, you might as well glue a USB thumb drive to the hard drive and be done with it. (And in fact, an md-like linux driver to combine two block devices in a manner like the above would be a great hack.)
"256MB should be enough for anyone." Where have I heard something like that before?
Most of us can be barely bothered to read the summary, let alone TFA... and you want us to google for a link?
Might as well ask for a never-ending supply of beer*, and 12 nekkid virgins to be awaiting your return home after work tonight to satisfy your every whim.
*or Mountain Dew, depending on your age/preference.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
http://en.wikipedia.org/wiki/Wear_levelling
Here is an alternate article for the slashdotted original:
Exactly. So the 900g figure simply means it took 900 times as long time to accelrate during the fall than it took to slow down when it hit the floor. Let's assume a fall from that height took 9 seconds (I could have computed the exact value if the height had been given in standard units), then it means it must stop in just 0.01 seconds when it hits the floor to have a 900g force. (Not completley accurate since the force during those 0.01 seconds is probably not constant, but you get the idea.)
Do you care about the security of your wireless mouse?
This really isn't about reads but writes. By using this they can collect writes better (so they have to move the spindle less), cache the writes here (so they can avoid spinning up the disk longer), and protect writes (write in to this, power goes out, data still safe... RAM wouldn't do that). There isn't really much point to this for reads, as just sticking a little more cache (say 64MB) on the drive would work just about as well there.
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
Normally flash has a 10^7 erase/rewrite cycles. (from text book) It might be more for the new-age tech. But it is far lower than magnetic drive anyway.
No, that's not correct. Samsung is shipping hybrid hard drives for over half a year now (see, for example, http://www.engadget.com/2007/03/07/samsungs-hybrid-hard-drive-hhd-released-to-oems/).
Recently, they even blamed Microsoft for the poor performance of hybrid hard disks on Windows Vista (in German, http://www.heise.de/newsticker/result.xhtml?url=/newsticker/meldung/97021&words=Samsung%20Hybrid&T=samsung%20hybrid)
The real world benefits of using flash as a cache layer between the harddrive and the computer, either through hybrid drives, don't seem to have materialized yet.
With my thinkpad there was an optional gig of flash that I ordered. After I downloaded the drivers and got it all set up, I found that there wasn't any noticiable difference in speed, or harddrive usage. However, I did notice that it interacted poorly with the "active protection" feature that stops the harddrive whenever the computer is in motion. Whenever the computer was unplugged, the flash cache was turned on, I could simply shake my computer (thus activating active protection) to get a blue screen.
Furthermore a little research showed that benchmarks on flash caches being sold right now offered no performance benefit whatsoever.
If there's no performance benefit, why are they trying to sell these things to people? I've seen some handwaving over the idea that flash *might* keep the harddrive from spinning most of the time and thus save battery life. However, when using the flash I saw no noticeable benefit.
Having an extra layer of cache in the system architecture seems like a good idea on paper, but in the real world the consumer is buying totally worthless pieces of hardware that do not improve performance one whit, and have never been proven to improve battery use.
What you are describing is a write-back cache.
Brain fart? Or I misconstrued you?
From TFA:
I am a bit surprised to find, that there is a market for exploding laptops..
The equations of motion can be found at
:-)
http://en.wikipedia.org/wiki/Equations_of_motion#Linear_equations_of_motion
In this particular case,
vf = vi + a * t
seems most appropriate (where vf is final velocity, vi is initial velocity, a is accelleration and t is duration of acceleration).
Assuming vf = 0 and solving for a, we get
a = vi/t (1)
Solving for t yields
t = vi/a (2)
"vi" after a 6-foot fall can be determined by using another of the equations:
vf^2 = vi^2 + 2ad
(where d is distance in meters, let's use 2 meters for 6 feet. We must assume that vi is zero.)
vf^2 = 2ad = 2 * 9.8 * 2 = about 40 m2/s2 (for simplicity).
vf = sqrt(40) m/s = about 6 (for simplicity)
For an object that travels at 6 m/s, we can use equation (2) above to learn how much time it must decellerate over in order to experience 900 Gs. 900G is (approx) 9000 m/s2 so we get
t = vi / a = (6 / 9000)s = 0.00067 seconds
So what we learn is that a disk that is dropped from 6 feet has a speed of 6 m/s as it hits the ground. Upon hitting, it starts deforming and if this is a reasonably linear process (which may or may not be the case) then a constant 900Gs throughout means that it took 0.00067 seconds to come to a complete stop.
Determining how many millimeters of the disk and/or ground got deformed during the decelleration is left as an exercise for the reader
sigs are hazardous to your health
The ideas behind this are applicable to any O.S. and there are proposed standard ATA commands to manipulate the Non-Volatile cache, see http://www.t13.org/Documents/UploadedDocuments/docs2007/D1699r4b-ATA8-ACS.pdf. I hope Linux and Mac hackers are working on it.
I'm not sure if the drive takes advantage of NV cache without specific O.S. support. Even without O.S. support, the drive could decide "You keep reading blocks X Y and Z, so I'll store them in NV cache" (drives already do this with their conventional RAM cache, typically 8MB) and "I'll keep your pending data writes in NV cache while waiting for the disk to spin up".
Windows Vista's ReadyDrive takes specific advantage of this feature: "During shutdown or hibernate all the disk sectors needed to boot or resume are pinned into the NV cache... Offsets within files and/or specific LBAs can be specified by the PC OEM in registry for pinning in the NV Cache". I converted the MS PowerPoint presentation http://docs.google.com/Present?docid=dcvvrqtp_13gj635t&fs=true (yay Google Docs, die PowerPoint DIE!).
=S