NAND Flash Better Than DRAM For PC Performance 205
Lucas123 writes "Adding NAND flash memory to a PC does more for performance than DRAM and costs less, according to a new study. As the price difference between the two memory types widens, NAND flash will become the memory of choice in the PC. The effects of NAND flash adoption are already being felt in the DRAM market, as revenue in 2011 is expected to decline 11.8%."
One Problem (Score:5, Informative)
NAND flash degrades over time and has a limited amount of program/erase cycles.
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You're very much a question talker, aren't you?
And anyway, the reason why you would use NAND as RAM instead of the current DRAM if they could work out the kinks is because NAND doesn't need power to maintain state. This means that you could be doing something on your computer, kill the power without any sort of warning at all, and then plug it in later and resume exactly where you were before. It would lead to, for instance, near-zero battery usage sleep in mobile devices; they would be able to almost shut
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"NAND doesn't need power to maintain state"
Electron leakage as you go lower in fab scale processes pretty much ensures that your statement is false.. This is why we're trying to move to OUM/OVM phase-change memory instead.
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Re:One Problem (Score:5, Insightful)
I work with flash daily, we make products that last 15 years with flash. Without large failure rates. The problem is not with flash. It's with the SSD implementation. It's the "let's replace harddisks with flash! and don't change anything else!" that causes problems. Because of this normal filesystems are used, that assume to be on spinning harddrives, which have no issue in writing the same sector twice, or just writing 1 sector at once. On flash on the other hand you need to do wear-leveling, and have large erase blocks. Both are handled on the SSD right now, and that's where it fucks up. It needs to maintain an internal mapping of all the flash, accounting for wear-level and shifting blocks around. One error in this internal management and your disk is junk. Even with your fancy journaling filesystem (ntfs/ext3,4/...) you are just 1 power failure away from losing your data.
Compact flash cards, SD cards, SSD, USB sticks all see this problem. So far we've only found a few suppliers of Compact flash cards which guarantee the internal management is safe, and we tested it and found it to be true. SD cards, I've a few broken "industrial grade" SD cards on my desk as proof that this is not the case. SSD is to large for our product, so I have no tests for these, but I expect the problem to be the same.
We use raw flash, with linux and JFFS2 or UBIFS. Which is a filesystem designed to run on flash, raw flash. Wake me when "SSD" offers that solution.
(TRIM is not a sollution, it's a workaround)
Re:One Problem (Score:5, Interesting)
Compact flash cards, SD cards, SSD, USB sticks all see this problem. So far we've only found a few suppliers of Compact flash cards which guarantee the internal management is safe, and we tested it and found it to be true. SD cards, I've a few broken "industrial grade" SD cards on my desk as proof that this is not the case. SSD is to large for our product, so I have no tests for these, but I expect the problem to be the same.
If you expect SSDs to have exactly the same problems as SD cards, you're a total moron with at best shallow expertise in the field. Go look up the specs of controller ICs used in SSDs and try to tell me with a straight face that they're exactly the same thing you'd get in a SD card, or even a very good CF card.
To pick just one example, do you know of any CF cards which compress all data on the fly in order to increase effective flash lifespan by reducing the total amount of data written? (Since the SSD controllers in question use hardware compression engines which can handle hundreds of megabytes per second throughput, this also has the nice side effect of increasing effective performance, unless you're storing incompressible data.)
We use raw flash, with linux and JFFS2 or UBIFS. Which is a filesystem designed to run on flash, raw flash. Wake me when "SSD" offers that solution.
Whatever makes you think the FTL (flash translation layer) firmware inside SSDs isn't designed to run on flash, raw flash? Whatever makes you think that a generic one-size-fits-all software solution like JFFS2 applied to whatever random flash memory you put in your embedded system is better than a SSD whose firmware has been tuned for the specific flash chips it was built with? (One of the fun things about NAND flash is that it's far from generic, especially MLC, and even more especially sub-30nm MLC NAND.)
More broadly, JFFS2 is one way to skin the cat, having a "drive" abstract flash into a generic block device is another. If you want low cost, low-to-medium performance, and probably not the best possible reliability, especially for heavy write loads, JFFS2 and friends will do just fine. If you want a real HDD replacement for non-embedded-systems, it's not even close to being the right solution. Which is why you don't see anybody trying to deploy flash-managing filesystems as HDD replacements.
The controllers used in real SSDs are expensive enough that it would be a huge win if you could toss them and just use a flash FS. There are lots of very good reasons why this has not happened and will not happen. Take your head out of your butt and get some perspective, right now you're a classic example of how a little knowledge is a dangerous thing.
(TRIM is not a sollution, it's a workaround)
No, TRIM is an attempt to improve performance which has been oversold a bit in the popular computer press.
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To pick just one example, do you know of any CF cards which compress all data on the fly in order to increase effective flash lifespan by reducing the total amount of data written?
You shouldn't be calling people morons "with shallow expertise", because if you actually understand how and why things break you would realize that your remark actually supports his point: which is all that fancy stuff makes it more likely for you to lose data.
Or worse, lose data without realizing it, see this: http://www.dslreports.com/forum/r25491097-Dell-Laptop-and-SSD-Time-warp-issue [dslreports.com]
http://forum.notebookreview.com/alienware-m17x/552728-fresh-os-install-ocz-ssd-r3.html [notebookreview.com]
To quote:
any firmware before 1.29 can result in you experiencing what OCZ refers to as "Time Warp" (you lose all info stored on drive since last boot - happens at random). 1.29 decreases likelihood of this happening, but does not eliminate the possibility.
If you don't notice that th
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this should be able to be abstracted away from the OS completely, have a capacitor large enough to power the drive long enough to flush the ram on power failure shouldn't be all that much required due to speed and energy efficiency of SSDs.
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Because of this normal filesystems are used, that assume to be on spinning harddrives
Worse still are cheap-ass SSDs that assume "normal" filesystems are being used, and corrupt your data if you aren't using windows [seagate.com].
Re:One Problem (Score:4, Interesting)
Care to tell us which flash storage cards (brand, capacity, name, etc) you tested which have safe internal management?
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(is FAT32 still used for these high >4GB densities?)
AFAIK, Windows does not like NTFS on a "removable" drive, so unless you make the CF card appear as a hard drive (which would be OK for Windows), you have to use FAT or FAT32.
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Well, an external hard drive is detected as a "hard drive", so it is partitioned and formatted like an internal hard drive. USB flash sticks and various cards in card readers are detected as "removable disk" and Widows does not want to create more than one partition and format it in NTFS.
Well, at least Windows XP does this.
No kidding (Score:4, Interesting)
It is far, FAR more important for your computer to have enough RAM than to replace a HDD with an SSD. At this point (and probably for a long time) flash is not replacing DRAM. You need to have RAM in your system for it to work. Flash replaces hard disks.
Well cool, HDDs are by far the slowest component these days. SSDs are have somewhere in the range of 2-5x the transfer rate they do and more importantly are an order of magnitude or more faster on access.
Well that still is no comparison to DRAM. DDR3 is 40x the transfer rate of even fast SSDs and about 4-5 orders of magnitude less access time. So you can't just have flash, at least not if you want a nice n' fast CPU.
Now in terms of practical usage I find RAM is way, WAY more important. If you don't have enough, some programs will just flat out not run. If your system is starved, paging kills the performance, even with an SSD handling the paging. Knocking in a good amount of RAM is the #1 thing you can do to keep your system running well and it is damn cheap.
SSDs improve responsiveness, don't get me wrong. I love mine and I'm happy to have them (though to be fair I wasn't willing to get them until I saw some on sale for $200 for 256GB). However it is a more minor improvement than having a system with plenty of RAM or a good CPU. I do notice some slowness to my non-SSD work system, but not much.
The other problem is even though flash is cheaper per GB ($2ish per GB as opposed to more like $9ish for DRAM) you need more disk space than memory. My laptop has what I consider a reasonable amount of both, that is 4GB of RAM and 256GB of SSD. My desktop has a ton of RAM, 16GB, and a moderate amount of SSD, 512GB. So the SSDs cost me a hell of a lot more, despite their lower per unit cost. I could easily recommend a 4GB or more RAM upgrade to anyone, I couldn't recommend an SSD big enough to hold a good amount of stuff.
Pretty much I only recommend SSDs if you've already maxed out your RAM. Spend your money on that first, then if you are still willing to bear the cost of an SSD, go ahead.
In that vein, I noticed more improvement on my laptop than on my desktop. No small part of that is likely the RAM. The desktop has RAM to spare, it can cache a ton of stuff. The laptop is not starved for RAM, but not does it have a massive surplus. The base usage on the system is about 1.5GB for OS and background services. Gives it maybe 2.5GB for caching when nothing else is running. Hence the SSD helps more.
Evict things from cache (Score:2)
Now in terms of practical usage I find RAM is way, WAY more important. If you don't have enough, some programs will just flat out not run. If your system is starved, paging kills the performance, even with an SSD handling the paging.
I think the idea is that with the faster access times of an SSD, the operating system will be able to evict things from the system's cache more quickly, leaving more RAM for applications to use.
about 1.5GB for OS and background services.
This is part of the problem. Handheld devices are still RAM-starved, which is why handheld devices run a different incompatible operating system. But small laptops are also RAM-starved, and they run a desktop OS for the sake of user familiarity despite having only 1 GB (source: Dell.com).
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3 or 4 GB of RAM on new systems? Seriously, why would you create a new system without being fully 64 bit and a minimum of 8mb of RAM, preferably in two slots with two more open? Not knocking your logic, just your implementation. History has shown this old man that RAM requirements go up faster than Moore's Law. 4GB of RAM is too low with Win7 aggressive caching, which is one of the very few advantages of it. Even the file servers (Linux) are using 24GB of ram so they can cache everything, and they were
Re:One Problem (Score:4, Informative)
Not to mention what TFA neglects is the simple fact that one doesn't need as much memory as they do storage space so comparing the two? More than a little pointless.
My interpretation of the article is as follows: In any given workload, you're likely to have a mixture of memory operations and disk operations. If, instead of putting all your money on RAM that will speed up your memory operations, you put part of it into an SSD that will speed up your disk operations, the overall performance for that workload will be better. Prefetching programs doesn't do nearly enough if the workload involves more disk activity than just loading the code.
Not sure I agree with the article, but the point is a lot better than you were making out to be.
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1) SSDs cost a lot more - you can get fair sized RAID for the price of one SSD.
2) SSD failure modes don't appear to be as graceful as they should be in theory - too often their failure mode is to become completely unaccessible. Whereas I've been able to recover some data from many failed HDDs,
3) SSD failure modes are weird - they have a "time warp" failure (google it) - the drive apparently goes back to the state it say a few days ago but otherwise works as normal. That's not confidence inspiring,
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Well, I'd put the system on SSD, and my own data at HD. Having the system on SSD speeds up things most, because for typical uses of the computer, user data is rarely the bottleneck. Moreover, the system partition is not written to very often, thus it should take longer to wear out. Finally, if the system partition has a total failure, you don't even think about rescuing data from it anyway; you just install the system again on the replacement disk.
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NSFW (Score:2)
No, but they're great in iPads [southparkstudios.com].
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so do humans.
Wake me up when NAND has a life-time 10% of an average human and we'll talk.
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Heh. My main computer's SSD, with the current write pattern, is expected to last at least 10 years before it starts to fail (before it hits the limit where manufacturer says the first chips might start to fail).
(well, according to this program [ssd-life.com] at least)
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"expected": So it could fail today or tomorrow.
So will some humans.
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Why thank you for pointing this out! This is so completely unlike HDD's which I've used for over 20 years now! You should write an article and post it to Slashdot [/sarcasm]
Sorry, was too big a temptation :)
Anyway, what you point out is true, and is exactly the same for harddisks. Which is why I have a server with 6tb in raid5 for storing anything important (and, I'll admit, a truckload of unimportant stuff).
Plus dropbox also works as a secondary backup system for some of my data (mostly code snippets and p
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NAND? Replace RAM?
Not until the read-writes are on the order of at least 5 magnitudes higher than they are now, and about 1/10th the access time of where they are now.
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Exactly what they want. Planned obsolescence.
From my perspective, NAND as RAM are already obsolete. Voting with my wallet, never going to buy as such (I ruined one of the first eeepc-es by installing a Linux and setting up a swap space. What I was thinking? 10 minutes later, I almost have a brick in my hands... salvaged only with an external SD card for storage).
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Sounds like you're saying first-generation NAND controllers are obsolete. Woohoo. Doesn't say much for the technology in general.
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No offense meant, but why the hell did you do that? If you bought a first gen eee, you knew what you where getting into, that it had a small SSD instead of a spinning platter drive, and since SSDs werent firstly introduced in the eee, the fact that NAND degrades and isnt a good choice for swap space was known as well.
I got a first gen eee as well, and did install linux as well, but instead of using swap, i just doubled the ram and disabled swap.
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No offense meant, but why the hell did you do that?
No offence taken. As an excuse for a stupid thing... I was doing it at wee hours in the morning.
Anyway, I wrote off the money for the extra SD card as "tuition fees" (as in "lesson learnt").
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Ah, a violation of the extended "dont drink and root" rule :)
sleepiness and installing stuff don't mix ;)
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Weird... I have done that too. Asus EEE 704 4G, with a swap space. I installed other operating systems a few times (Reset the original a few times, Debian Sid, Ubuntu 10.10/Netbook edition, Debian Squeeze which is what it's currently running) It's still going strong. My wife was in hospital for a full 8 months and it was her (only) computer during that time and she used it every day to email/surf/watch movies/listen to music. During that time it did have a small swap partition (By now, I switched to swa
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Unless you use any one of the various distros that have swappiness set to say... 60 like Ubuntu, in which case it will use swap even when NOT RAM constrained.
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At least back in the XP days, swap space ("the paging file") was used heavily. Around the time 1 GB memory sticks became affordable, I found that turning off the paging file completely resulted in a massive speedup. I have no idea if recent Windows versions work the same way, but it wouldn't surprise me. Ubuntu (as mentioned below) has swappiness set very high by default (swappiness = how aggressively the OS tries to swap things out). I usually set it to something like 10 (don't swap unless memory is mostly
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Re:One Problem (Score:5, Informative)
NAND flash degrades over time and has a limited amount of program/erase cycles.
Spinning rust degrades over time and has a limited amount of write/erase cycles.
Total bullshit. Please try to have a clue when you try to be clever. There is no wearout mechanism which eventually makes it impossible to alter magnetic domain orientations in spinning rust. You can keep doing that forever. In practice, the lifespan of a HDD is limited by mechanical failure or the death of the controller electronics.
The difference between NAND flash and spinning rust is that it's faster. Early evolutions of NAND flash reached the limits of their write cycles therefore. Modern evolutions of NAND flash make it more durable and reliable than spinning rust in every instance - and the speed and storage density is just a bonus.
Good god, you're clueless. Every evolution of NAND flash makes its durability and reliability worse, not better, due to some fundamental physics problems with NAND technology. The only thing keeping NAND viable is throwing ever-stronger ECC codes at the problem (decreasing the effective density gain from each process shrink by consuming more bits in error correction overhead). Write/erase cycles also keep going down, not up.
And then there's the fun phenomenon called "read disturbance". If you haven't guessed just by reading the phrase, this means you can alter the state of a bit cell in the latest and greatest generation of NAND flash by reading it (or its neighbors) too many times. Whee!
Don't confuse the application of stronger and higher overhead techniques for managing the problems with NAND with it being a super-memory with no flaws. It has a lot of issues.
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Good post...
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"Modern evolutions of NAND flash make it more durable and reliable than spinning rust in every instance"
Except I have functional hard drives from 1980. Show me an SSD or NAND that's still going strong after that amount of time.
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Forgive me, but you've shifted the context.
I was using RAMdisk for storage over 30 years ago. It's great performance storage, but the whole forgetting everything on power loss is an issue. We've done ten workarounds that I know about.
You kids these days, you think you invented everything.
I'm confused (Score:2)
There would have to b
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You're missing the point:
Nobody is talking about what's faster or cheaper. They're comparing apples and oranges -- and telling you which to buy.
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Here's the crux:
Obviously this is moot
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4-8Gb of RAM will allow the OS to prefetch pretty much everything you use on a daily basis and then some, while 4-8Gb of NAND
The first of these is only true in theory. You may only access 4-8GB of data per day, but predicting which 4-8GB that will be is hard. Operating systems get the low hanging fruit, but the difference in performance from disk caching hits diminishing returns after about 1GB. With 8GB, you're likely to have memory free, because the OS can't make good decisions about what to cache.
The second half is completely missing the point made in the summary. 8GB of RAM may give more of a performance increase than
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and 64GB of flash makes a much bigger difference to performance than 8GB of RAM.
except it doesn't. That's like saying 2TB of 5.25 Floppies make a bigger difference to performance than an 8MB HDD. Bigger storage space does not equal faster speed.
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except it doesn't.
Yes it does, that's the entire point of the conclusion of the study in TFA. Beyond a certain point, RAM only makes your computer faster because it's being used as disk cache. Cache quickly hits diminishing returns, and beyond that point making the persistent storage faster is a more noticeable improvement. If you can add a big enough flash drive that almost everything the user ever touches will be in flash, then this gives a much bigger improvement than a small increase in cache. A few disk cache misses
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Cutting off your own foot with an axe and cauterizing the wound is more cost effective than going to a doctor and having your diabetes treated for 30 years. Guess which one I'm picking.
Caching disk data in Flash instead of DRAM (Score:2)
I suspect that what they're talking about is the effect of caching data from your disk drives in Flash instead of DRAM, and also letting you swap data out of DRAM into Flash instead of disk. Flash is cheap enough that for typical applications, you can cache most of your active data there, not having to wait for rotating machinery.
Windows 7 is supposed to have some feature that manages this in an intelligent way - so you can speed up your machine for a year or so by adding a $10-20 memory stick. (I'm no
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"Windows 7 is supposed to have some feature that manages this in an intelligent way - so you can speed up your machine for a year or so by adding a $10-20 memory stick. (I'm not running Win7, so I haven't tried it - but my laptop has an SD card slot, which would let me leave a card in there full time, without it sticking out like a USB stick.)"
I've tried it on multiple systems, with fast USB sticks - Superfetch is much faster and more efficient. Only problem there: Many of the current generation (Sandy Brid
BS Article (Score:2)
The article gives zero useful information and a link where you can buy the actual study. What was the pricing used for the comparison of $1 dram versus $1 nand? Surely this is OS dependent as well.
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Who do they expect to buy this study? It has a rotten order about it...
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Well, it's obvious, that Flash is superior swap:
-) it's random access. The huge impact of seeking (measured in ms) is gone.
-) it's relatively fast at reading/writing too, compared to normal hdd.
So yes, it's obvious that adding flash for swap makes sense.
Now if flash-swap can substitute RAM depends naturally a little bit on the workload.
But 2x4GB DIMMs cost your around 44€ here around. A small SSD in 230-270MB/s range costs 62€ for 32GB.
So you get about 2.8x as much "capacity" for SSD compared to R
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FTA :
After reviewing a "wide range of DRAM and NAND configurations," as well as nearly 300 industry-standard PC benchmarks, the researchers concluded that even at today's prices, a dollar's worth of NAND flash improves PC performance more than adding a dollar's worth of DRAM.
How in hell's name do they conclude this? Do they extrapolate from zero or something? I mean, if your machine starts out with say, 2-4GB of RAM, which is usually enough for running most of your applications (minus cache), what do you think is gonna make more of a difference? Adding RAM will just cause the OS to cache more, so you're just limited by HDD-DRAM speed. On the other hand, if you stick a NAND in there, you'll still be caching but at the speed of NAND-DRAM, which is considerably faster, plus
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Okay, have anyone here experienced flash wear out? Hmmm, no hands raised. Performance issues with modern OS and modern (as in last year introduced stuff) SSD? No hands again.
It's absolutely correct, that flash can wear out. Flash as in flash memory cells. Modern SSDs have quite a bit of controller logic to handle this. Plus replacement blocks. So yes, if you use it extremely intensively, e.g. as swap, SSD may (or not) give up after 2 years or so. Hint: I'm used to swapping hdds once per year, to avoid data
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"Okay, have anyone here experienced flash wear out? Hmmm, no hands raised."
That's because you answered yourself without letting anyone speak up, you fucking moron.
I've had multiple flash types fail miserably on me.
Consider this a big raised hand plus a slap to your ignorant mouth.
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Caching more is pointless since it only caches when you load things the first time. Adding a 32 GB SSD as an OS drive did more to accelerate my system than going from 4 GB to 8 GB RAM did. For desktop use where each app load will pull in a ton of libraries from all over the drive it is ideal and at my usage pattern it will be a good 10 years before I even start to see the drive wear out.
Details: 8 GB RAM, 32 GB SSD for OS and applications, 1 TB for data.
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People are using Windows on SSD's just fine. Windows 7 actually disables the behavior you speak of on an SSD, anyway.
Most SSD's seem to die from controller failure way before the actual flash cells are dead.
die from controller failure? (Score:2)
Why should the controller fail, especially, why should the controller fail before the flash?
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You have to ask the makers of the devices, but if I have to guess: the flash cells are designed by the top engineers of each fab+their partners and go through very extensive testing and validation cycles. The controllers are a complicated electronic designed for maximum speed by the lowest bidder and rushed to the market, and which additionally has to interact with similarly designed devices.
Human failure will kill the devices way before low-level physics will.
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Because it's badly designed. Or more, it's designed for speed, not data safety. Read that again, SSD is designed to give you data fast, not to give you the right data all the time. The controllers need to account for wear-leveling and shifting around data so it uses less erase blocks. (A sector on a spinning harddisk is 512bytes, an erase block on a flash chip can be as large as 128kb)
The controller needs to maintain internal management of the flash layout. A virtual mapping so to say. 1 error in this mappi
Comment removed (Score:3)
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wasn't that the potential for memristor technology if that ever pans out? Except its storage, RAM and logic?
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Basically, TFA is saying that it will be awhile before we go back to a unified cache that's both RAM and storage (like core memory).
Actually, core memory was used exactly as RAM and not as storage, even though it did have data retention capability (obviously, as it was based on ferromagnetic effects). The actual storage was done on mechanical devices. Heck, back in those days, you had some fast rotating drums with lots of reading heads - a hard drive of sorts, except that it had fast data access and throughput, but limited capacity. Even this, seemingly hard-drive-like device, was used as RAM only.
Correlation is not causation (Score:3)
The former is not the cause of the latter. The rise of mobile devices with less DRAM in them is more likely to blame: less people are buying new PCs and Laptops when their phones and/or tablets can do everything they need.
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The rise of mobile devices with less DRAM in them is more likely to blame: less people are buying new PCs and Laptops when their phones and/or tablets can do everything they need.
The more likely theory is that computers continue to live longer and have reached the point of "good enough" that end users do not feel compelled to replace a working, 6 year old computer.
A bit confusing (Score:4, Insightful)
I think all they mean is that dram isn't really all that cost effective as a data cache. For data that one intends to export out the network. Storing that data on a SSD, assuming it's a relatively static data set (which most is), uses far less power and costs less than purchasing an equivalent amount of DRAM (and the much larger mobo required to hold that DRAM). The access times are plenty fast enough to still saturate the network. That's all. Not rocket science.
This has been known for several years. Replicate a small server with 8-16G of ram + a 160G SSD + a 2TB HDD sits right on the sweet spot. In fact, even 4G of ram would probably be fine. The idea is not to replace your hard drive but instead to insert another layer of cheap caching to avoid having to maintain a complex, expensive, power hungry HDD storage system just to get better throughput.
-Matt
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Woosh!
Hits the sweet spot for what?
The very first lines of the post you're criticizing describe the use case:
I think all they mean is that dram isn't really all that cost effective as a data cache. For data that one intends to export out the network.
Matt's point explained succinctly: SSD speeds are faster than network speeds. SSD cost per Gb is less than RAM cost per Gb. Ergo, SSD are a more cost-effective cache, because the extra speed from RAM is useless.
A firewall clearly doesn't fit the "data that one intends to export out the network" use case.
NAND Flash worse the DRAM (Score:2)
Is the assertion really hybrid hard disks and turbo memory are having a noticable negative effect on the DRAM market?
Trying to imply a relationship between two markets by realitive growth is especially rediculous considering explosion of the smart phone market which relies entirely on flash.
The only thing more rediculous about TFA is the idea NAND is in any way a suitable replacement for DRAM.
Server market (Score:2)
I see this article as being myopically focused upon "main memory in portable end-user devices."
DRAM is going to stay vital for at least the server market, and I would guess the desktop market too (for as long as desktops last). Your iPad 3, maybe they have a point, but server apps would work current NAND into an early grave. The cost savings would be greatly offset by the service outages.
And since "the Cloud" is the new big thing, that means that DRAM is going to be around for a while. I don't see how the m
Pirates and Global warming (Score:2)
If SSDs appear and DRAM goes down it could aso be that there are now more subnotebooks or ultraportibles in which DRAM is a power consumer and HDs are too big? It could be that MS, under the pressure of the first netbook wave which contained linux has shown reason and put out Windows 7 in opions which allow to run it on normal machines. I mean. Just thinking.
I personally dont see Flash replacing DRAM soon. I see that DRAM memories stop to grow for other reasons.
Let me say it that way round: i see that my PC
They should make a mini-PCIe device for laptops (Score:2)
It would be a couple GB of flash that is accessible to the OS as a block device. Then, let the OS use it for paging and for caching of frequently access files or blocks.
There should be a branding campaign so that consumers know that it is extra memory that will speed up their machine. Call it something like "turbo memory."
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It exists, it's called Thunderbolt.
http://en.wikipedia.org/wiki/Thunderbolt_(interface) [wikipedia.org]
It's a combination of displayport and PCIe.
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It exists, it's called Thunderbolt.
Nope: mini-pcie is a different standard (also wire compatible with PCIe) designed for internal usage in small form factor devices. It's much more suitable for a laptop SSD than thunderbolt.
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They should make a mini-PCIe device for laptops
They do. Runcore make a 128GB mini-pcie SSD. I have one. It is very nice.
SSD ReadyBoost ? (Score:2)
I'm assuming MS is keeping an SSD version of ReadyBoost as a Windows 8 "new feature". This should offer a very good price/performance ratio.
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I think there's a limit to how big your readyboost cache canbe before it starts to degrade performance - if you're reading all the time, then it's fine, but when you start to write you have to write to both your SSD and the backing store or invalidate the cached data you've just modified.
Besides, a USB flash drive comes in sizes up to 128Gb, and they're a lot cheaper than SSDs. If you have a SSD, install it as a drive!
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I was thinking, indeed, of a very small SSD delivering most of the performance of a full-size one, at a fraction of the cost. Something along the lines of 80% of the performance for 20% of the size, and cost.
I'm trying out USB3 readyboost, 7 seems to grab 4GB max.
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ReadyBoost has nothing to do with paging.
NAND/DRAM/HDD (Score:2)
The right balance of NAND, DRAM and an HDD yields better results than DRAM and HDDs, study finds
So.. they have NAND, DRAM and HDDs, and they choose to kill.. DRAM? What? If something is going to fade away it is the HDDs..
I actually read the "article" (Score:2)
They give no information about how they measured and came up with this: a dollar's worth of NAND flash improves PC performance more than adding a dollar's worth of DRAM. The closest they come to explaining it is this: After reviewing a "wide range of DRAM and NAND configurations," as well as nearly 300 industry-standard PC benchmarks
Total garbage. After working with systems that have huge amounts of RAM in them, I can only conclude they are basing this off of Microsoft's paging algorithms. Put the swap/page
Did everyone here read a different article than I? (Score:2)
I'm coming in a bit late to this debate, but I got a completely different take on what the article was about than just about every post here.
Everyone here seems to have used the article as an excuse to drag out the old "tired" debate of NAND vs HDD (and DRAM in this case) and which is better (from a technical perspective). I didn't see anything in the article that compared these on a technical front. The article was about the NAND market vs the DRAM market going into the future. It makes total sense to me.
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Why ? The extra RAM could be used as additional disk buffers. The fact that your current utilization is only 75% doesn't mean that extra RAM won't be used. It could be that the OS has a strategy to keep some f
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I read the same article. The problem is that the entire article should be rendered as fine print underneath a HOLLYWOOD sized YMMV billboard.
Also the TCO on SSD taints the economics: failure modes are changing at a speed that gives even a hard core geek a rational ignorance skin rash. There was a nice post above on the physics of desperation. I can add DRAM without a major update to my mental catalog of high-performance electronics failure modes.
Also I don't get the economic argument in the first place.
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"Adding NAND flash memory to a PC does more for performance than DRAM and costs less" isn't a statement about markets. It's a statement about how the use of certain technologies affect the overall performance of a PC.
But it doesn't say that in the article. That's what the summary says. Everyone who's been here a while knows that the summary is usually way off the mark as to the true content of the story.
SSDs are the best improvement to make TODAY (Score:2)
The greatest performance limiter of today's top-of-the-line computers is the mechanical hard disk. Although the article may have some concepts screwed up (I assume), the one upgrade that makes the greatest _apparent_ improvement in performance is switching from an HDD to an SSD. Yes, it's true that more DRAM helps, but any decent NEW system today already comes with 4GB of RAM (2GB if you really cheap out). 4GB is overkill for most users, so switching to an SSD will have a greater impact on general perfor
Huh? (Score:2)
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I wouldn't know. IU assume all such posts are goatse and don't bother to go there.
That well is poisoned, and I don't trust it ever.
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I've been telling people this ever since SSD drives came out. A system with 2GB of DRAM and an SSD drive will easily outperform a system with 8GB of DRAM with a traditional Hard Drive in every benchmark that matters to the average user. It'll boot far, far faster, programs will load instantly, defrag's are a thing of the past, virus scans take mere seconds instead of hours, and by the time your SSD drive is used up, you probably need a new computer anyways
Unless you need to use 8GB of RAM to complete your work. At which point your totally screwed. I'm pretty sure using an MLC SSD as virtual memory at this scale voids your warranty.
Now mix two Corsair SSD drives in RAID 0 like i've done for the past year along with 4GB of DRAM and the PC absolutely screams, there is no comparison, none whatsoever between traditional hard drives and SSD drives. Even (6) 15k RPM SCSI drives in stripe RAID can't keep up with the I/O of 1 SSD.
A pair of mirrored 7200 RPM disk drives with 32 GB of RAM and a warm cache runs circles around your setup. It would also be more reliable, cheaper and provide 10x the storage capacity.
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A pair of mirrored 7200 RPM disk drives with 32 GB of RAM and a warm cache runs circles around your setup. It would also be more reliable, cheaper and provide 10x the storage capacity.
Depends entirely on the workload. The HD drives will lose if:
a) The working set exceeds 32GB. If the accesses are random, they will lose by 2-3 orders of magnitude.
b) Whenever there is a need to commit or sync the writes to disk. On a normal system, that will happen every few seconds. If you disable that, your reliability argument is gone.
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I think that's an admission that modern software is too bloated and virtual memory on a computer kills performance.
Hasn't learned what flash is, maybe? (Score:2)
I'm more inclined to think the author has just learned what RAM is and doesn't yet understand the difference between flash RAM and dRAM.
The nether reaches of my memory (Score:2)
A quick web search doesn't bring up any examples, but I remember when flash first came out, some of the manufacturers insisted on calling it "flash RAM" in their ads.
I also remember the arguments on the BBSes, and the conclusion that EEPROM was already different enough from UVEPROM and other ROM as to call into question the ROM part of the acronym, and that "flash ROM" seemed a bit like an oymoron. Enough people have complained about calling it flash RAM that the maufacturers have gone to "flash memory". Bu