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The Benefits of Hybrid Drives

Zonk posted more than 7 years ago | from the best-of-both-worlds dept.

193

feminazi writes "Flash memory is being integrated with the hard disk by Seagate and Samsung and onto the motherboard by Intel. Potential benefits: faster read/write performance; fewer crashes; improved battery life; faster boot time; lower heat generation; decreased energy-consumption. Vista's ReadyDrive will use the hybrid system first for laptops and probably for desktops down the road. The heat and power issues may also make it attractive in server environments."

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193 comments

Finally... (3, Insightful)

Cherita Chen (936355) | more than 7 years ago | (#15814865)

This is not a new idea, nor is it new technology... This has been a long time coming.

Re:Finally... (2, Insightful)

TwentyLeaguesUnderLa (900322) | more than 7 years ago | (#15814872)

But it's still pretty cool - a new way to integrate existing technologies, bring them together to make computers work better. I thought TFA was an interesting read, even though it didn't have anything particularly earth-shattering in it.

Re:Finally... (1, Interesting)

NitsujTPU (19263) | more than 7 years ago | (#15814934)

I don't think that's what he's driving at.

People have been talking about doing exactly this technique for quite a while. It just never hit the mainstream. I even think that there were a couple commercial implementations of this, but I'm not sure on that last point. It is definitely talked about in research papers on filesystems that I have read.

Re:Finally... (4, Interesting)

grammar fascist (239789) | more than 7 years ago | (#15814898)

This is not a new idea, nor is it new technology... This has been a long time coming.

The prices finally fell to where it's economically feasible.

Personally, I like Intel's idea better (embedding the flash memory in the drive controller), because it should work just fine with existing drives. It might also be upgradeable, but I'm not holding my breath.

Re:Finally... (4, Insightful)

Knetzar (698216) | more than 7 years ago | (#15815289)

I don't like that idea, since if a system failure occurs and I want to move my harddrive to another system, there is a chance that the harddrive is in a bad state. Where as if you have th flash integrated with the HDD, then the write buffer is with the disk (as it should be).

Catastrophic Failure of Flash Memory (4, Interesting)

reporter (666905) | more than 7 years ago | (#15815012)

The technical specifications of the flash memory in my USB drive says that it is guaranteed to work for, at most, 100000 (i.e., one followed by 5 zeros) writes. People do not talk about this limitation, but I have seen this limitation written into the technical specifications of the flash memory in many devices [globalspec.com] .

The hard drive in my Compaq x86 workstation has been humming nicely for more than 5 years. Due to the nature of my work at the institute, the number of writes to the hard drive have easily exceeded 100000 during that time.

Using flash memory as a fast cache for the hard drive will increase the performance of the drive but will decrease the overall life of the drive. Someone will be awfully upset when she makes a final save of her million-dollar PowerPoint presentation for the CEO and discovers that the save is the 100001st write to the hybrid drive.

Hopefully, the engineer who designed this hybrid drive has, at a minimum, integrated an LCD counter and a tiny speaker into the drive. The counter shall display the running total of the number of writes to the flash memory. The tiny speaker shall beep like crazy when the total exceeds 99900.

Re:Catastrophic Failure of Flash Memory (5, Funny)

servognome (738846) | more than 7 years ago | (#15815026)

Hopefully, the engineer who designed this hybrid drive has, at a minimum, integrated an LCD counter and a tiny speaker into the drive. The counter shall display the running total of the number of writes to the flash memory. The tiny speaker shall beep like crazy when the total exceeds 99900.

It was in the original engineering design, but the lawyers said it would be cheaper to just include a warning in the fine print of the warranty.

Re:Catastrophic Failure of Flash Memory (-1, Flamebait)

Shai-kun (728212) | more than 7 years ago | (#15815048)

Hahaha! You're funny.

Re:Catastrophic Failure of Flash Memory (5, Insightful)

Volante3192 (953645) | more than 7 years ago | (#15815053)

The technical specifications of the flash memory in my USB drive says that it is guaranteed to work for, at most, 100000 (i.e., one followed by 5 zeros) writes. People do not talk about this limitation, but I have seen this limitation written into the technical specifications of the flash memory in many devices

But, on the other hand, how often do you write to your windows folder? There's the monthly update, the occassional reg hack, but all in all, once it's established, that's a pretty static area of your drive. I could see this as an incredible benefit to system files, which, as has been discussed oft here before, the big reason for this.

Loading your PPT file in flash won't help bootup. Loading that fuster-cluck of the system32 folder, though, would.

Someone will be awfully upset when she makes a final save of her million-dollar PowerPoint presentation for the CEO and discovers that the save is the 100001st write to the hybrid drive.

Backups? Alternate locations? If this is what it takes for them to learn the necessity of redundant copies, it's even better.

There should be some level of safeguard built in that anything user created should be stored to the magnetic part of the drive, my documents, program files, but they should have this anyway. I mean, nothing like the last save and then having to call Dell because your drive is spitting out an Error Code 7...

Re:Catastrophic Failure of Flash Memory (5, Interesting)

Osty (16825) | more than 7 years ago | (#15815339)

But, on the other hand, how often do you write to your windows folder? There's the monthly update, the occassional reg hack, but all in all, once it's established, that's a pretty static area of your drive. I could see this as an incredible benefit to system files, which, as has been discussed oft here before, the big reason for this.

Depends on what you're doing. For example, if you run IIS, your log files (by default; you can change this) are in %WINDIR%\Sytem32\LogFiles. That's going to have a lot of writes. Any new hardware or software installation may cause writes to %WINDIR%. There's a lot of other stuff that legitimately writes to %WINDIR% like installing a new printer (think roaming -- you may print to a different printer every day), the .NET Global Assembly Cache, Visual Styles and themes, and a whole lot more. Whether these things should be in %WINDIR% or not is a different question. The point is that using flash for %WINDIR% under the assumption that you'll not write there very often is a little naive. Perhaps Vista reorganizes %WINDIR% somewhat so that fewer processes need to write there.

There should be some level of safeguard built in that anything user created should be stored to the magnetic part of the drive, my documents, program files, but they should have this anyway. I mean, nothing like the last save and then having to call Dell because your drive is spitting out an Error Code 7...

All of this is a moot point anyway, because this use of flash is only as cache. Anything written to the flash drive should eventually be flushed to the hard drive. Similarly, if you've exhausted your write cycles and try to write to the cache, it should seamlessly catch the fault and go directly to hard drive. In that case it would be nice to give an occasional notice that your flash chip is exhausted and you need to replace it, but you should not risk losing any data. I'm not a big fan of on-board flash simply because it may be unreplaceable. Any onboard flash chips should not be surface-mounted, but socketed like RAM, CPU, or the clock battery. That will require some standardization on sockets, but as long as there are only two or three different options and the designers of said options let others build chips using that interface (*cough*Sony*cough*) it shouldn't be a problem.

In the long run, I think computer manufacturers will love this. How likely do you think your parents will be to replace their onboard flash when they run out of write cycles? The average consumer will just buy another PC for a couple hundred dollars rather than buying a new flash chip and installing it (or paying someone to install it).

How soon do you think the conspiracy theories will start up that manufacturers like Dell are intentionally shortening the life of onboard flash through factory "testing"?

Re:Catastrophic Failure of Flash Memory (1)

miyako (632510) | more than 7 years ago | (#15815054)

It seems like the sane design would be to use the flash memory if available, but otherwise function like hard drives do today. In otherwords, if the flash memory craps out, you can still read and write to the drive, although with a performance hit.
Given, as you mention, the limited number of writes on these, it might also be neat to have using the flash as a supplement to increase speeds something that can be turned on or off from the OS. I could see that being useful in a number of ways, if it was written in a sane manner that wouldn't simply kill the flash memory too quickly from exessive rights.

Re:Catastrophic Failure of Flash Memory (4, Funny)

evilviper (135110) | more than 7 years ago | (#15815069)

Someone will be awfully upset when she makes a final save of her million-dollar PowerPoint presentation for the CEO and discovers that the save is the 100001st write to the hybrid drive.

Yes. Everyone knows flash RAM will explode in a gigantic fireball on the 1st attempt to write to it, once it has gone beyond spec.

Re:Catastrophic Failure of Flash Memory (1)

OverflowingBitBucket (464177) | more than 7 years ago | (#15815084)

The hard drive in my Compaq x86 workstation has been humming nicely for more than 5 years. Due to the nature of my work at the institute, the number of writes to the hard drive have easily exceeded 100000 during that time.

During which you weren't purchasing new drives for your machine.

I can see why hard drive manufacturers might like the idea of a limited-life-span device...

Re:Catastrophic Failure of Flash Memory (2, Insightful)

Cerium (948827) | more than 7 years ago | (#15815154)

True enough, but what customers are going to pay more for a drive that costs more AND needs to be replaced more often when the only advantage is a possibly insignificant performance increase?

I doubt many people are going to take this route when existing technologies (RAID comes to mind) work fine for those who absolutely need the extra performance (or rather, have convinced themselves they need it [Hi, owner of that $7,500 gaming rig!]).

Re:Catastrophic Failure of Flash Memory (0)

Anonymous Coward | more than 7 years ago | (#15815254)

"True enough, but what customers are going to pay more for a drive that costs more AND needs to be replaced more often when the only advantage is a possibly insignificant performance increase?"
That is even not that... you will primary get faster boot times... cause the flash will be filled up with Windows' files.

Re:Catastrophic Failure of Flash Memory (1)

Bacon Bits (926911) | more than 7 years ago | (#15815124)

Yes, it just means you add a new level of storage. Essentially, flash is less than primary but more than secondary storage. Since it has write limitations, you need to make sure that it is mostly WORM files, such as OS and program files. Write-intensive files such as user data files, temp files, transactional databases, paging files or swap partitions, etc should remain on magnetic media. Flash offers very high read performance, plain and simple. It is not a replacement for a hard drive any more than a DVD-RW is or a tape drive is. Linux will very easily work in this type of environment. You mount the partitions you mount read-only on your flash media, and then mount your userspace, /tmp, /var, and swap partition on magnetic.

Re:Catastrophic Failure of Flash Memory (4, Interesting)

flooey (695860) | more than 7 years ago | (#15815128)

Using flash memory as a fast cache for the hard drive will increase the performance of the drive but will decrease the overall life of the drive. Someone will be awfully upset when she makes a final save of her million-dollar PowerPoint presentation for the CEO and discovers that the save is the 100001st write to the hybrid drive.

The thing to note is that that limitation is per flash block, not for the whole thing. So for a 1 GB flash component, given perfect block mapping, you can write around 100 TB of data to it before it wears out. With a 150MB/sec transfer rate, it would take more than a week of continuous writing to write that much. As well, modern flash can withstand a couple million writes, extending the life to several months of continuous writing. Given that this would generally be containing operating system components, which are read often but written to rarely, the lifespan of the memory should be no worry at all.

Re:Catastrophic Failure of Flash Memory (1)

caseih (160668) | more than 7 years ago | (#15815159)

That's really 10000 writes to a single cell on the flash chip. All flash memory has built-in algorithms to statistically spread out those writes over all the cells of the chip, so it's not like if you wrote a file 10000 times you'd have an instant failure. If you only write to on average, say 10% of the disk, then you wouldn't see a failure for probably 100000 writes. Given a 4 GB flash chip, the average write is probably just a few megabytes, so works out to even longer time between failures. Still not a huge lifetime, but not as short as you say.

Re:Catastrophic Failure of Flash Memory (3, Informative)

adrianmonk (890071) | more than 7 years ago | (#15815214)

The technical specifications of the flash memory in my USB drive says that it is guaranteed to work for, at most, 100000 (i.e., one followed by 5 zeros) writes.

I thought I'd seen specs an order of magnitude larger than that in many cases, but the problem still may not be as bad as you think in many cases even if it is as bad as 100000 writes. The reason? Flash devices have systems built in to their controllers specifically to deal with these problems. The mechanisms may vary, but the ones I know about are wear leveling [wikipedia.org] and excess capacity (beyond the capacity that the device reports to the operating system) that can be pressed into service when a block fails.

Briefly, wear leveling means that if you write to the same logical address over and over, the controller will map that write to different physical addresses each time. That means that you can't wear out the device by rewriting the same file over and over again; instead, you only add a little bit of wear to each physical block on the flash device. The concept is a little bit like rotating the tires on your car except that it's a more dramatic win since write patterns can be much more uneven than wear on tires on a car.

The other mechanism for mitigating the effects of limited flash life is putting excess capacity aside (so that it's not reported to the OS) to be used when a physical block does fail. Since it's a matter of probability just which write will cause a given block to fail (meaning that some will fail after less than 100,000 writes and some will probably last much longer), even with wear leveling it's unlikely that all blocks will fail at once. It should be easy to tell when the pool of spare blocks is nearing exhaustion and give you advanced warning that your flash device is wearing out. So in that sense, it is actually safer than hard drives, which tend to fail without warning.

Finally, this whole thing reminds me of the reaction some people (mostly audiophiles) had to compact discs, and digital audio in general, when it first began to replace analog systems. There was some resistance to the technology because it was sure to sound artificial: after all, you were taking the music apart into discrete steps and putting it back together again. Obviously, a system which broke a waveform down into a discrete step can't ever really reproduce exactly the same waveform as the original. And that's true, but what they missed was the fact that analog systems can't ever reproduce exactly the same waveform as the original either. Both systems have limitations, in this case distortion of the signal, and the true question should be not whether the proposed new system has limitations, but whether the limitations of the new system are worse or better. (The answer to that may depend on the intended use.)

I think the same thing applies to flash devices. Yes, you may have a hard drive that has been humming along for 5 years without a problem, and that's fairly common, but hard drives do fail. When I was a system admin, I saw my fair share of them. (I've seen a few since then too.) The key in the case of flash is probably to get in place a nice warning system that can take advantage of the ability to notice that spare blocks are being depleted and warn the user when failure of the device is nearing. I haven't researched it carefully, but perhaps SMART [wikipedia.org] would be useful for this in some applications, such as where flash is replacing hard disks.

Re:Catastrophic Failure of Flash Memory (1)

Kaktrot (962696) | more than 7 years ago | (#15815221)

The technical specifications of the flash memory in my USB drive says that it is guaranteed to work for, at most, 100000 (i.e., one followed by 5 zeros) writes. People do not talk about this limitation, but I have seen this limitation written into the technical specifications of the flash memory in many devices.

Actually, that depends on which kind of flash memory it is. I would assume that they would use the newer, cheaper, more robust NAND flash [wikipedia.org] . 100,000 cycles was the low estimate, at least according to Wiki. NAND would have an endurance of 1,000,000 to 10,000,000 erases. Not forever, but that's a big difference. I am also cautiously optimistic of more durable flash before too much longer.

Re:Catastrophic Failure of Flash Memory (1)

dynamo (6127) | more than 7 years ago | (#15815321)

How about if it just becomes a normal drive once the flash dies?

Re:Catastrophic Failure of Flash Memory (0)

Anonymous Coward | more than 7 years ago | (#15815395)

Due to the nature of my work at the institute, the number of writes to the hard drive have easily exceeded 100000 during that time.
Are you sure you have made over 500 writes a day to the exact same area for say 2000 consecutive days? Let's say you have: doing a simple CRC check after writing enables the system to immediately discover failure, mark the bad blocks and relocate the file. You have only lost the part that was used for this bit of data, not the entire flash memory. The check doesn't cost that much time (a lot of it is happening anyway) and besides, you will have plenty of usable area anyway, as flash will cost next to nothing in the near future.

Re:Catastrophic Failure of Flash Memory (1)

greg1104 (461138) | more than 7 years ago | (#15815409)

You're describing this disaster scenario as if it's a new problem introduced by this technology. I've already had plenty of demos I was doing for important people blow up because of a hard drive error (I'm just lucky that way). Which is more likely: that you'll hit the flash write limit, or that the mechnical part of the drive will crash and burn? My experience with hard drives suggests they're none too reliable right now, and anything that can reduce the amount of time they spend moving around has a potential to improve the mechanical failure rate.

With wear leveling and some spare capacity to replace early bad bits, 100,000 write cycles for each bit works out to quite a bit of data with a decent size chunk of flash. An analysis I liked at http://www.sudhian.com/index.php?/articles/show/68 6/3 [sudhian.com] suggests a typical office worker will get 33 years out of a hybrid drive, while even someone who writes 6GB of data every day should get 4 years out of the drive. There are plenty of drives out there that aren't even warrantied for 3 years right now.

As for too much writing induced disasters, you just have the flash part of the drive start throwing SMART errors when it gets low on useful bits, the same way drives right now can report when they're running out of spare sectors to relocate bad drive sections into. That should catch the issue well in advance of a flash crash.

When you run the numbers it doesn't sound that difficult to create a flash-based design that would likely outlast the mechanical parts of a standard hard drive.

Re: about the limitation of flash memory (0)

Anonymous Coward | more than 7 years ago | (#15815276)

ofcourse what will be written in the flash memory will not be the data, but program code what is seldom changed.

Old? (1)

Mr EdgEy (983285) | more than 7 years ago | (#15814870)

Old news.. but still, it all depends on how well the drive caches. If it's writing useless data it's worthless... a swapfile to "slower" memory could be nice.

Re:Old? (1)

Kuroji (990107) | more than 7 years ago | (#15814887)

Windows creates an immense swapfile anyway - why not just get the system to do it on either a designated part of the hard drive, or on a USB 2.0 flash drive?

Actually, has anyone tried that? I expect you could see a decent increase in performance that way.

Re:Old? (5, Informative)

nmb3000 (741169) | more than 7 years ago | (#15814950)

Windows creates an immense swapfile anyway - why not just get the system to do it on either a designated part of the hard drive, or on a USB 2.0 flash drive?

Actually, has anyone tried that? I expect you could see a decent increase in performance that way.


Windows' swapfile usage is pretty similar to the way Linux does swap, except that Windows uses a file instead of a partition. By default it's 1.5 times the amount of RAM installed in the system and is made all at once to ensure a contiguous file. On systems with plenty of RAM it's still good to have because it means the OS can commit to having plenty of memory for applications which request a lot, most of which they might never use. Without a page file 10-20% of physical memory is wasted because the OS has committed to having it (think Photoshop, etc).

I don't know how well the pagefile would work on a USB drive since if you're using much swap you're already seeing serious degradation. Besides, flash drives still suck at write speeds, being many times worse than even an old IDE drive. That's the biggest problem with integrating the two technologies I would think--making sure that you don't introduce bottlenecks due to stuff like that.

USB Flash, Swap, Windows Vista (2, Informative)

Zan Lynx (87672) | more than 7 years ago | (#15815083)

Haven't any of you been playing with the Vista betas? Vista has a sort of swap file / prefetch feature that you can enable on USB flash drive. Vista first benchmarks the device, to determine if it is fast enough. Then you can create a sort of swap file on it, as big as you like.

It's part of the Vista SuperPrefetch.
http://www.windowsitpro.com/Windows/Article/Articl eID/48085/48085.html [windowsitpro.com]

Re:Old? (1)

kevlarman (983297) | more than 7 years ago | (#15814945)

since flash memory is only good for a limited number of writes, i would think that a swap file is thing you want to put there.

Hybrid Drives! (5, Funny)

Sixtyten (991538) | more than 7 years ago | (#15814873)

Will they increase fuel economy as well?

Re:Hybrid Drives! (1)

Kryptonian Jor-El (970056) | more than 7 years ago | (#15815061)

imagine a day when our drives will be free of fossil fuels and will be powered by electricity alone!!!...wait a minute...

Re:Hybrid Drives! (1)

Toba82 (871257) | more than 7 years ago | (#15815231)

Since part of the point is to save power, yes.

Oh, you were just making a pointless joke to get modded up. Carry on.

Re:Hybrid Drives! (1)

grammar fascist (239789) | more than 7 years ago | (#15815243)

Will they increase fuel economy as well?

I hear the worst part about them is refilling the bits after they run out. The cells are large and clunky and you have to wear special gloves to do it. Even worse, it actually takes many times more bits to create a cell than the cell stores, meaning that it's more economic just to get them from the pump!

What a waste.

Been there done that (1)

ganjadude (952775) | more than 7 years ago | (#15814886)

I remember in 2002 when I was enrolled in the CISCO CCNA classes, we were playing around with a hybrid console. It was a small HD maybe 5 gig and small flash drives working in conjunction. Ok so it wasnt EXACTLY the same but it worked on the same principal. I only wish I could remember the model number...

Re:Been there done that (1)

ChaoticChowder (971057) | more than 7 years ago | (#15814925)

If I had a little more info, I might be able to help you remember. Information about whether it was a switch or a router would be nice. Now, I do know that some 7200 series routers come with the ability to write configs to a hard drive. I guess it really depends on the modules you put in the Cisco equipment(it seems to me that they have a module for just about anything.)

Re:Been there done that (1)

ganjadude (952775) | more than 7 years ago | (#15815126)

Wow.... it was a router, I think it might have been the 7200 or a 9X00 series it was too long ago.

Re:Been there done that (1)

ChaoticChowder (971057) | more than 7 years ago | (#15815174)

Yeah, I had the pleasure of working with 7206 VXR routers for a couple of years. The only reason I remember is because it was out of our traditional setup and it took me couple of minutes to figure out where the configs were being saved. I think I remember the drive being 10 GB and 32 MB of flash...

Maximum Writes for Flash Memory? (2, Interesting)

graphicartist82 (462767) | more than 7 years ago | (#15814896)

Most flash memory i've seen (such as the USB keychain drives), have a rated maximum writes before the memory starts having problems.

Am I missing something here? How are they going to overcome this if they plan on using the same type of memory for disk cache?

Re:Maximum Writes for Flash Memory? (1)

KingJackaL (871276) | more than 7 years ago | (#15814929)

Unfortunately, I have a sinking feeling their 'fix' may just be to ensure that:

MeanWritesBeforeFailure / AverageWriteRate > WarrantyPeriod

...here's to hoping the longevity of flash memory being produced is improving with time.

Re:Maximum Writes for Flash Memory? (1)

NitsujTPU (19263) | more than 7 years ago | (#15814974)

Yes. There are companies offering solid state storage devices commercially as high-speed replacements for hard drives. BitMicro is one of them, and offer terrabyte RAIDS of the stuff.

Re:Maximum Writes for Flash Memory? (2, Informative)

phoebe (196531) | more than 7 years ago | (#15814995)

They are not flash though, the solid state storage devices use banks of DIMMS with backup batteries and hard drives to save state when power failure occurs.

Flash isn't a terribly fast medium either, hence all the marketing over 12x, 20x, 50x compact flash cards in the digital camera market.

Re:Maximum Writes for Flash Memory? (-1, Troll)

Anonymous Coward | more than 7 years ago | (#15814981)

Why isn't the UN "shocked" at decades of unprovoked and intentional Islamic aggression against Israeli civilians? Why isn't the UN "shocked" at how Islamofacist pigs respond to Israel's concessions and withdrawls with paper promises? By unconditional ceasefire, what the Europussies and Islamopussies mean is a ceasefire from Israel while Hezbolla and Hamas continue to snipe at them with wildly inaccurate rockets with the sole intent of killing as many Israeli civilians as possible. Fuck Islam, and fuck Mohammed.

Re:Maximum Writes for Flash Memory? (-1, Troll)

Anonymous Coward | more than 7 years ago | (#15815103)

Maybe you'll think differently after Israel nukes Iran, Russia nukes Israel, America nukes Russia, China and Russia nuke America,India and Pakastan nuke each other for no apparent reason, and we're all fucking dead. Or maybe not.

Re:Maximum Writes for Flash Memory? (1)

Joebert (946227) | more than 7 years ago | (#15814990)

How are they going to overcome this if they plan on using the same type of memory for disk cache?

Simple.
By commenting out the section of source that checks the read/write count registers.

Re:Maximum Writes for Flash Memory? (5, Informative)

DDLKermit007 (911046) | more than 7 years ago | (#15814992)

An age old method called write leveling. In practice it usualy doesn't work since most people do it with USB thumb drives and/or flash memorycards which are all removed on a regular basis so the reader/writer of the media gets changed allot or the controler doesn't impliment write leveling. As such the write leveling never really gets done very well. With a system like this the write leveling would be exact and the flash memory would end up outlasting the moveing parts of the hard-disk. Also as parts of the card went bad the controler would skip over those sectors in the future which would lead to it working even longer. Even one part of a regular hard disk goes bad and your boned completely.

Re:Maximum Writes for Flash Memory? (1, Informative)

Anonymous Coward | more than 7 years ago | (#15815180)

eh? since when did bad disc sectors make a hd die? regular magnetic drives have been working around bad sectors long before the inroduction of flash. no, the problem with magnetic hd drives are the movings parts that die which elimates the drives completely, which will still exist in these hybrid drives. until a pure flash hd comes out, all these hybrids does is create a minor improvement in performance. flash unfortunitely still has a bit to improve in performance(faster then hd speeds are expensive for flash), size, and cost. as stated by you, write leveling will make flash last quite a while, probably to the life of the hd but i don't see how useful the addition of flash would be instead of say a flash slot (you already have a ram slot, a connector for hd, why not add a flash slot into the mix that is far more flexable where the os could be read from it or something along thsoe lines) (i'm aware the idea has been put out, just can't remember what intel called it)

Re:Maximum Writes for Flash Memory? (1)

Antony-Kyre (807195) | more than 7 years ago | (#15815251)

I agree. A bad sector on a spinning disc drive doesn't ruin the drive. The drive dying ruins the drive, more or less. Well, unless you're going to spend thousands on doing one of those data recovery things.

Solution: Doing a RAID so if a drive does go bad, there's the second drive. Just replace. (I don't know too much about RAID, so correct me if I'm wrong.)

The advantage of flash is what the article says though. Faster O.S. booting. Hybrid drives is a really good idea. Something fast to put the O.S. onto meaning no more 3-5 minute boot-ups for Windows.

Re:Maximum Writes for Flash Memory? (1)

DDLKermit007 (911046) | more than 7 years ago | (#15815267)

Yet a bad sector on an HD usualy is not caught until the user does a complete scandisk of the drive so the bad data continues to march on. With flash based systems the bad sector is caught on the first write. Bad sectors aren't much of an occurance anymore with HDs though. The actuall moveing components is what I was refering to which there are many to have die on you. Also if you actually RTFA this type of application would be for LAPTOPS primarily to save power (not slap another power hungry drive in). Of which the only laptops I've ever seen have RAID is the overpriced Alienwares.

Re:Maximum Writes for Flash Memory? (1)

retep (108840) | more than 7 years ago | (#15815352)

No, you're wrong. The write leveling is done by the controller on the USB thumb drive itself, not the computer it's attached too.

Ref: http://www.storagesearch.com/siliconsys-art1.html [storagesearch.com]

Re:Maximum Writes for Flash Memory? (1)

djdavetrouble (442175) | more than 7 years ago | (#15815010)

How about adding one of those red jewels from Logan's Run ? When the jewel starts flashing, you send it of to Carousel and it can Renew!
Oh wait, they just died in Logan's Run too..

Re:Maximum Writes for Flash Memory? (2, Informative)

earnest murderer (888716) | more than 7 years ago | (#15815028)

Am I missing something here?

Yes, durability has improved tremendously. Also, they aren't using it for swap. Most of the files that will get cached here are things the OS developer knows (or the system obsreves) are going to be asked for frequently. Data will also be saved here sometimes to avoid spinning up the disk.

The sum of these writes are not going to exceed the durability (some millions of writes was the last spec I saw) of modern flash in any reasonable time frame.

Also, if someone is abusing the technology or just keeps the same drive around that long the whole system doesn't fail, it just becomes a bog standard disk. Since a write failure is known at the time it is written you don't even loose data.

Re:Maximum Writes for Flash Memory? (1)

crmartin (98227) | more than 7 years ago | (#15815129)

Also, it's a write limitation. There are a lot of files (the gcc executable, say) that get written very rarely, like once, and read thousands of times.

Re:Maximum Writes for Flash Memory? (0)

Anonymous Coward | more than 7 years ago | (#15815040)

From the paper at Microsoft.com (available at http://www.microsoft.com/whdc/device/storage/hybri d.mspx [microsoft.com] , have a read)

NV Cache Flash Wear
NAND flash memory is rated for a limited number of write-erase cycles before individual cell failure. The result is that heavy use of the NV cache could deplete the available capacity over time.

To avoid the possibility of this happening, H-HDD vendors are likely to employ wear-leveling algorithms that spread the wear across all of the available flash blocks and extend the useful life of the entire cache. Also, ReadyDrive algorithms have been designed to limit the writing and erasing of contents in the NV cache, so even for the smallest NV cache sizes, the useful life of the cache is expected to extend beyond the useful life of the device it is packed in. If the NV cache does experience any wear, it will result in a smaller capacity NV cache and will eventually be treated as a standard HDD by Windows Vista. For larger NV cache capacities, proper wear leveling will ensure that this outcome is even less likely.

Re:Maximum Writes for Flash Memory? (1)

rew (6140) | more than 7 years ago | (#15815089)

There are several things. First: flash chips are easy to make in such a way that some cells have a much longer longlivety. So many flash chips come with say 10k max writes, but a specific 1% of the chip is specified to last at least 10 times longer.

Secondly, things go bad if you write the same spot repeatedly. Don't do that then. This is much easier to implement for a harddisk-write-cache than for an USB stick. In the write-cache write something like: "write-ID 1234, sector 4567, data:..." // write-ID 1235, sector 9876, data" etc. When the disk powers up, you just start writing at the lowest write-ID. All flash-sectors get used equally. No need to do balancing (which they have to do for the USB sticks to prevent say the FAT from wearing out before the rest does).

Thirdly, you could think a bit about what goes into the cache and what doesn't. If the disk is spinning, just write to the disk. Suppose you have a 100Mbyte flash backup, you will need to write a total of 1 terabyte of data to the flash before it wears out (at 10k cycles per cell). Take into account that this is for power-saving on laptops. On that laptop you'll install an OS, and never touch that region of the harddrive again. That's static data. When you work on the laptop, your work will be saved occasionally, but how long untill that adds up to a terabyte? Suppose you save a gigabyte a day: the terabyte will last you three years! So even IF you don't get smart about bypassing the cache if possible, the lifetime of the flash is easily comparable to that of the drive.

Last, if you keep count of how many times you've used the flash you can fallback to "the old way" if your count (or the number of ECC-fixups required) indicates that the flash might be nearing the end of it's life. You shouldn't lose any data.

Re:Maximum Writes for Flash Memory? (1)

aztracker1 (702135) | more than 7 years ago | (#15815099)

I am guessing that it will be dedicated to OS system, and boot files that don't change often... not for a swap file.

Re:Maximum Writes for Flash Memory? (4, Interesting)

Eivind (15695) | more than 7 years ago | (#15815134)

You're missing that the typical comercial flash-module is built to withstand 1 million writes or more.

A 1GB flash-module bein written to *constantly* (24 hours a day, 365 days a year) with a sustained speed of 5MB/s would thus wear out sometime after 6.5 *YEARS* of continous operation.

I'm guessing you can see why this problem is purely hypothethical for 99.99% of all laptops out there. You don't write to disc *constantly* and even if you did, you don't typically use the laptop 24/365, and even if you did, having a laptop-drive fail after 6-7 years is normally not a showstopper.

If, more realistically, the laptop is used 8 hours/day 250 days/years, and writes to disc 10% of the time when turned on, then the 1 million writes to flash will get reached after aproximately 30 years.

Even these numbers are high -- my laptop is heavily used as a developer workstation, and it certainly does not write to disc 10% of the time it is turned on.

Magnetic-RAM. (2, Insightful)

Anonymous Coward | more than 7 years ago | (#15814899)

MRAM would have been a better choice.

A good idea (2, Interesting)

apathy maybe (922212) | more than 7 years ago | (#15814905)

This is a good idea (even if it is old). In fact flash memory is so small that you could scrap hard drives altogether if you had enough money.

Imagine twenty 1 gig flash memory cards in a row ... less space then the equivelent hard drive.

Re:A good idea (0, Redundant)

Heembo (916647) | more than 7 years ago | (#15814991)

NYET, Flash memory has a much reduced shelf-life compared to hard-drived in terms of maximum writes before it degrades, not to mention hard drives are way cheaper than flash. Good old hard drives are much more reliable in the long term and cheaper, at least for now...

Re:A good idea (1)

LordLucless (582312) | more than 7 years ago | (#15815177)

Imagine twenty 1 gig flash memory cards in a row ... less space then the equivelent hard drive.

Now imagine 500 1 gig flash memory cards in a row - I bet the 500GB HDs beat them out on form-factor quite considerable. Not to mention the other problems with flash as a replacement for harddrives - read/write times and the relatively low write-limit are the things that jump to mind.

another "benefit" (2, Interesting)

plasmacutter (901737) | more than 7 years ago | (#15814910)

another benefit of integrating flash memory onto the motherboard is the ability of hackers to hack your motherboard independently of the OS, and for friendly companies like microsoft to protect you from yourself by placing code they control in places you cant access on your machine.

no, I dont like this one bit, it's just a huge security hole begging for exploitation by hackers and DRM vendors.

Re:another "benefit" (1)

Frogbert (589961) | more than 7 years ago | (#15814944)

What the hell are you talking about? Most modern day motherboard integrate flash memory in the form of a flashable bios. Hackers don't abuse this because it is such a narrow target, every motherboard is different.

Regardless, this article is about flash in hard disks.

Re:another "benefit" (3, Insightful)

plasmacutter (901737) | more than 7 years ago | (#15814965)

Hackers don't abuse this because it is such a narrow target, every motherboard is different.

exactly, every mobo is different.. this sounds like something which could make its way in as a standard part of windows computers.. much less narrow a target.

Re:another "benefit" (4, Interesting)

plasmacutter (901737) | more than 7 years ago | (#15814948)

I hate to reply to my own post but look, it's not offtopic.

flash memory is persistant. Unless you provide open apis to allow anyone to develop applications to wipe it, there is no real way to confirm anything that gets stored on it is actually removed.

Every platform, but especially windows, has a history of security exploits, and now the viruses will have somewhere to hide where they will be much harder to dig out, and anyone wanting to implement DRM could build an OS designed to hide critical components of it by burying it on the flash memory.

Re:another "benefit" (0)

DAldredge (2353) | more than 7 years ago | (#15814988)

And the technical ability of the typical /. user continues its downward spiral.

Re:another "benefit" (2)

plasmacutter (901737) | more than 7 years ago | (#15815006)

please illustrate to me exactly how I am wrong, otherwise please don't decry my post as technically inept.

I really am interested in how exactly the hypothetical I put forward is not possible, it would certainly ease my mind, but from my substantial time weeding out viruses and malware, experience has shown that if you are unable to delete every part of it it will grow back like a friggin weed.

Re:another "benefit" (1)

spauldo (118058) | more than 7 years ago | (#15815145)

One of the key points of cache is that if you change something on the disk, that overrules the cache. That's implemented in hardware.

Disks have cache now, although it's volatile. All this should change is that the cache will be there when the system boots. Sure, getting a virus in there will be just like if you had a virus on your hard drive, but any changes to the disk should be changed in the cache as well by the controller. The system itself probably won't have any way of directly accessing the cache itself, unless the ATA standard is expanded.

All that, of course, applies to the hybrid drive setup. The other idea, where the cache is on the motherboard, might be implemented differently, and might be cause for alarm. You can't really tell, but unless they're going to break a few fundamental ideas behind the ISA, there should be little to worry about.

Less expensive and probably just as effective (3, Informative)

keith134 (935880) | more than 7 years ago | (#15814955)

Plug in a USB or Flash drive and mount it as a non removable drive (drivers exist for this purpose...google them) then set your page file and temp files, etc. to the flash drive.

Re:Less expensive and probably just as effective (1)

Arramol (894707) | more than 7 years ago | (#15815082)

The problem with this is that you're then bottlenecked by the speed of the USB bus. USB 2.0 is only capable of 480 Mbit/s, which is slower than PATA's 1064 Mbit/s.

USB speed: http://en.wikipedia.org/wiki/USB#USB_compared_to_o ther_standards [wikipedia.org]
PATA speed: http://en.wikipedia.org/wiki/Serial_ATA#eSATA_comp ared_to_other_buses [wikipedia.org]

Impracticle in large data storage... (2, Insightful)

Fallen Kell (165468) | more than 7 years ago | (#15814956)

The solid state portion of the drives are really only good for data that will not change often. That section suffers from limited number of re-writes before the data integrity degrades. The hybrid disks work well mainly for the primary system OS disk and that is really just about it. The kernel and main OS components will rarely change (patches and kernel updates are the only times). This is why boot times are increased using these disks, because the OS and kernel is contained on the faster solid state memory...

Again, in an environment where data is constantly being written and deleted, these disks will fail a lot sooner.

Re:Impracticle in large data storage... (1)

Matthias Wiesmann (221411) | more than 7 years ago | (#15815050)

In some sense, I have the feeling we have gone full circle. What this amounts to is having the operating system and core libraries in some sort of pseudo-ROM device, that can be read fast and written a limited number of times. This is not so different from the classical macintosh computer that had a large part of the OS in ROM, the Mac classic had even a bootable disk image in ROM, plus ça change....

How is this redundant when 15 mins BEFORE others?! (1, Insightful)

Fallen Kell (165468) | more than 7 years ago | (#15815142)

Hey mods next time look at the timestamp before you mod redundant. Just because the other posts replied to a post before mine doesn't mean that the information contained in those replies came before my information did.

preference (2, Insightful)

spykemail (983593) | more than 7 years ago | (#15814975)

I'd prefer something longer lasting (and faster) than flash memory.

Re:preference (1)

cb0nd (893473) | more than 7 years ago | (#15815116)

Why not make it cheaper too?? This reminds me of a piece from the Hennessy and Patterson Computer Architecture book. In the chapter about memories, it says that a memory should be very fast, persistent, large and, why not not make it cheap, while you're at it. Yes, my friend, people have thought about this before. If someone found a better solution, people would use it, as surprising as that might seem.

Re:preference (0)

Anonymous Coward | more than 7 years ago | (#15815160)

MRAM might fit the bill... in several years. Right now freescale makes half-meg MRAM chips.

Not applicable to server environments (3, Interesting)

pestilence669 (823950) | more than 7 years ago | (#15814998)

"...The heat and power issues may also make it attractive in server environments..."

Not necessarily... perhaps during boot time. These potential savings are reserved for end-users who aren't doing anything data intensive. Last time I checked: database, web, email, and file servers are all data intensive... meaning that the drives will have to be spinning.

Hybrid drives do less in a server environment than a RAM disk. They can help boot faster, which is great for disaster recovery. If heat & power are a huge concern, flash drives, that are here now, solve those problems.

Re:Not applicable to server environments (1)

Knetzar (698216) | more than 7 years ago | (#15815299)

In an enterprise environment, if your database server or web server is often reading from the disk, then chances are you have a major performance problem. Disk I/O should be limited in any environment where you want high performance.

I can see this being very helpful when writing logs though. Instead of keeping the drive constantly spinning, it can just write to the flash memory and only occationally spin the drive up to dump that to disk.

They forgot one... (3, Insightful)

mattmacf (901678) | more than 7 years ago | (#15815000)

Potential benefits: faster read/write performance; fewer crashes; improved battery life; faster boot time; lower heat generation; decreased energy-consumption.

What about increased reliability? I realize a lot of this might depend on how the flash memory is interfaced, but it would be awesome to have a small built in flash chip capable of live backups of critical data. With say a spare gig of memory on the hard drive, it should be more than feasible to have data of certain folders (e.g. My Documents and system folders) in the off chance that your hard drive actually does fail. Being able to boot directly to the flash chip would be great in emergencies, and a copy of DSL/Puppy Linux/*Your favorite recovery tool* would be perfect to store there. Bonus points if you can easily (i.e. without a soldering iron) swap the flash chip to a fresh drive and do a Stage 1 Gentoo reinstall from scratch.

Come to think of it, the possiblities of RAIDing these things together could be interesting as well. With a RAID 1, all but the most paranoid wouldn't need to include the flash memory in the mirror. Or, should the flash memory get sufficiently large (say, 20-25% of the hard drive size), you could use the flash memory as dedicated parity in a RAID 4 array. Obviously this means squat if you can't interface the flash memory properly, but hey, at least the possibilities are there.

Another benefit... (4, Funny)

mbstone (457308) | more than 7 years ago | (#15815014)

Another benefit of hybrid drives is, you can use the carpool lane even if you're by yourself.

Past Its Time (0, Redundant)

distantbody (852269) | more than 7 years ago | (#15815038)

I think that this would have been a much relavant product if it was released 10 years ago, when flash memory was much harder to come by. But I would say we're less than one upgrade cycle away from completely solid state drives anyway, the ones that several manufacturers have been showing of over the past year and due very soon. I say don't bother with this concept that is a decade too late and soon to be obselete anyway. Why Linux sucks #42104: [SHIFT] + ["] ! = "

Not in most servers... (3, Interesting)

evilviper (135110) | more than 7 years ago | (#15815051)

The heat and power issues may also make it attractive in server environments.

No, it won't. Servers have large ammounts of system RAM, which is far faster than flash on the hard drive bus could ever be. They also have battery-backed RAID controllers, meaning flash would be a step down, not a step up.

This is only really useful in notebooks.

Re:Not in most servers... (2, Insightful)

QuantumFTL (197300) | more than 7 years ago | (#15815209)

Servers that don't access much of the disk (say, less than 1GB or whatever the size of the flash cache is) the majority of the time would benefit from this the same as laptops, by letting their disks spin down.

Also fast restart is especially good for critical servers as a method of reducing both planned and unplanned downtime. I know at lylix.net [lylix.net] , we will be getting one of these as soon as Gentoo Linux properly supports it - you don't want an Asterisk box down longer than it has to be.

Finally! Something Vista will have first! (1)

Ohreally_factor (593551) | more than 7 years ago | (#15815058)

Vista's ReadyDrive will use the hybrid system first for laptops and probably for desktops down the road.


Run, Vista! Run! Don't let those bullies Linux and OS X catch you!

Are standard file formats fine for use on flash? (2, Interesting)

Chonine (840828) | more than 7 years ago | (#15815117)

Are the standard NTFS or Ext3/Reiser/Whatever optimized for use on hard drives? If flash drives start appearing as main system drives, would new or modified versions of file systems help in any way? Or are modern file systems abstract enough to where they dont deal with all the little fiddly-bits? I don't know enough about this area, but it would seem to me that a new hardware device to store files may benefit with a change in the way the OS uses it.

Re:Are standard file formats fine for use on flash (4, Interesting)

I kan Spl (614759) | more than 7 years ago | (#15815188)

Most filesystems are in fact optimized for use on magnetic media. Ext3 uses algorithms to place data on the disc in order to minimize the amount of waiting done for data.

There are research filesystems that are optimized for this kind of a hybrid environment. These were written for MEMS insetead of flash, but the basic ideas are nearly the same.

http://www.ssrc.ucsc.edu/proj/mems.html [ucsc.edu]

Disclaimer: I work there. I may be biased.

Where to put the flash? (4, Interesting)

Michael Woodhams (112247) | more than 7 years ago | (#15815135)

The article discusses this. Intel want to put it on the MB, the drive manufacturers want to put it in the drive. A third option is to attach it separately and externally (e.g. a USB flash drive.) A final option would be to (e.g.) have a compact-flash-card (or similar) socket on the hard-drive, and users provide their own flash.

To my mind, the logical place to put it is on the drive. This is where the useful caching information is most easily available. (Which sectors are read/written how often? Which reads are often delayed by waiting for the disk to spin up?) This is also where you can make the process most transparent. The drive's firmware can make the system "just work", like a standard HD, but faster - whatever the OS, no drivers needed. (Although you'd possibly like to have drivers to give the OS more control over what is flash-cached.)

Re:Where to put the flash? (2, Interesting)

Locutus (9039) | more than 7 years ago | (#15815207)

how about using CF and a CF->IDE adapter for desktops and hang the adapter off the IDE bus. CF based PCcard adapters in laptops maybe? You can do this today and IIRC, CF cards have builtin wear leveling. move your /boot onto this for quicker boots and/or put your swap here and have quicker restores from hibernates.

LoB

Hybrid Momentum (1)

Doc Ruby (173196) | more than 7 years ago | (#15815179)

I like the part best where these hybrids fund the R&D for pure transistor drives without moving parts.

Excellent for servers but what does linux support? (1)

QuantumFTL (197300) | more than 7 years ago | (#15815186)

At we host many Asterisk VPSes, and because our customers rely on us for their phone service, any downtime, even planned well in advance, is something we try very hard to avoid. Because downtime from security patches is inevitable, this would be a big win for us, and a good selling point, so using it seems to be a no brainer. [lylix.net]

My question is - what kinds of support can/will the linux kernel have for this? We run Gentoo Linux as our host OS, and I cannot see us migrating to Windows for the forseeable future. I searched a bit online, and found this ask slashdot story [slashdot.org] , but no authoritative answer. Anyone?

Re:Excellent for servers but what does linux suppo (1)

QuantumFTL (197300) | more than 7 years ago | (#15815191)

Well, I guess we know why the preview button's there... good thing I code better than I post, otherwise I'd be fired!

SPAM (0)

Anonymous Coward | more than 7 years ago | (#15815285)

I thought Digg was bad.. then i saw this guy.

Damn, can't show off! (3, Funny)

kickdown (824054) | more than 7 years ago | (#15815208)

Damn. The RSS feed made me think this might be about hybrid _cars_, not hard drives. I was already dreaming of making clever comments about how cool it is to own a Toyota Prius. Now I make whiny comments about getting it wrong instead. Damn. Mod me down for futility and insignificance.

Suspend to disk + flash for better boot times. (2, Interesting)

Chonine (840828) | more than 7 years ago | (#15815229)

It seems like there is a huge demand for faster booting systems, but so few people use suspend to disk (hibernate for windows, goes by other names too). Shutting down and booting are faster, and it uses *no* power when off. It seems to me that some people are overly fixated on faster boot times, so long as no interesting software tricks such as suspend are used. Why is that? Many people want a faster booting computer, but refuse to do so with anything other than a traditional boot. I understand the limitations and the need to do a traditional reboot from time to time anyways, but suspending to disk is a great feature that is here now, that doesnt even need ACPI or any sort of power management doo hickery.

Flash is great but even with its random access speeds, the throughput isn't much better than drives, and so I don't see such a huge boost in boot times from flash alone. To have your cpu do all of that work every boot seems a bit rediculous. Reading a 512+ MB file into memory and a few adjustments, you are back to where you were.

(As an aside, can anyone tell me how BeOS was able to boot in only around 7 seconds for me a decade ago, to a fully usable desktop? From fully off to fully usable, that was nuts.... what can modern operating systems do to approach this?)

Re:Suspend to disk + flash for better boot times. (1)

llyenn (873664) | more than 7 years ago | (#15815336)

BeOs...fond memories... Booted that fast for me too, on a Celeron 400 with 64 megs of ram...ran like a champ to...damn shame

Re:Suspend to disk + flash for better boot times. (0)

Anonymous Coward | more than 7 years ago | (#15815398)

You may debate whether RISC OS is a modern operating system, but it can boot to a usable desktop in seven seconds. The longest waits are for DHCP, USB and PCI. If you could scratch those, you could be up in under 5 easy.

The core of RISC OS (including its Desktop components) is typically kept entirely in flash memory (or ROM if you are using Adjust, OS 4 or earlier.)

Re:Suspend to disk + flash for better boot times. (1)

cnettel (836611) | more than 7 years ago | (#15815410)

I love hibernation. BUT, putting the first 256 MB or so on flash, together with a BIOS which could initiate booting before the disk is done spinning up, would be even better.

The Allison Hybrid Drive. . . (0)

Anonymous Coward | more than 7 years ago | (#15815284)

has lots of benefits! http://www.shadetreemechanic.com/allison_hybrid_dr ive.htm/ [shadetreemechanic.com]

1)Faster startup times.
2)Lower noise.
3)Fluid-coupled technology.
3)Better power efficiency.

FTA: "This is pretty incredible technology."

By using more of these we could reduce energy usage, pollution, and global warming!

Coupled with an HOV lane, it may even result in faster transfer rates!!

Looks like a job for linux! (0)

Anonymous Coward | more than 7 years ago | (#15815396)

I hope the flash goes straight on the motherboard, and can be made to operate independently of the hard drive. Damn Small Linux only takes up 64 MB on the disc and ~100 MB of RAM (I could be off). With that 512 MB of flash straight on the motherboard, I'd be able to boot up and suspend instantly! Now, if they'd start making laptops with OLED screens, just think of they battery life!
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