Lucas123 writes "Intel is planning to launch its native flash memory module, code named Braidwood, in the first or second quarter of 2010. The inexpensive NAND flash will reside directly on a computer's motherboard as cache for all I/O and it will offer performance increases and other benefits similar to that of adding a solid-state disk drive to the system. A new report states that by achieving SSD performance without the high cost, Braidwood will essentially erode the SSD market, which, ironically, includes Intel's two popular SSD models. 'Intel has got a very good [SSD] product. But, they view additional layers of NAND technology in PCs as inevitable. They don't think SSDs are likely to take over 100% of the PC market, but they do think Braidwood could find itself in 100% of PCs,' the report's author said."
When given similar performance but a slightly higher price, i would prefer the SSD. I can't take the flash to the next PC as i can do with the SSD. Hard disks have a highe life expectancy than mainboards (i usually find some good use for old HDs, i never did for old mainboards). Unless the SSD will cost 2-3 times as much as the flash on the mainboard, i believe SSDs will still be used. But maybe this will lead to lower SSD prices.
I can't take the flash to the next PC as i can do with the SSD.
Not really a big deal; if it becomes commonplace, most PCs will eventually have it (or something like it) as standard anyway and you won't be bothered about it.
"(...)if it becomes commonplace, most PCs will eventually have it (...)"
Which opens an interesting hole. That flash on motherboard will hold some data to speed up system startup. That means first n opened files. With that flash big enough it will also hold quite a lot of user documents. Unless documents can be marked as "not to be cached" it will add extra headache when getting rid of old systems. We have it already with 419ers buying old PCs and smartphones, gangs dumpsterdiving, etc.
Also try to explain to customers that they will need to erase flash they cannot see in system (and will most probably not even know about it!) or destroy the chip before throwing away old system. With HDDs it's quite hard and those are big, visible and has been around for ages.
Seems to me that this article is a thinly-veiled marketing trick. Somebody publishes a paper, "Will Intel product A beat Intel product B?", and presto, we've got buzz about product A which doesn't even come close to competing with product B (which is a market leader, dontchaknow), and increased buzz about product B. Then, people chime in with their arguments and counterarguments about which product is better... and Intel wins no matter what. Both product lines are probably going to succeed independently of one another.
That said, Braidwood sounds awesome to me, especially because my servers talk to a storage box over NFS, and fast onboard cache sounds great to me. But, I want fast local storage too, and 16GB is nothing, so I want large-capacity SSD drives. I really don't see these as competing products. This is just a slashvertizement. Move along, folks.
That said - I'm more worrying about the consideration about exhausted flash on the motherboard. Have all avenues actually been considered here, or is that a built-in best before date that new motherboards will have?
Actually not. It is going to store quite permanently only some files used to speed up system processing. There is not going to be any journals, and the filesystem will be highly optimised for this kind of usage. That is from press release I read somewhere. So even MLC will last long time as writes will be very limited. Only issue is that to drive costs down controller is also going to be scaled down so no great magic as with SSDs. So if somebody hacks that flash to use as HDD it will wear quite badly and quickly.
If a 16GB Brainwood used a revolving cache, where any data not already in flash was read from disk and written over the oldest data in flash, then you would see very few erase cycles per day per block. You would need to do more than 16GB of disk IO to eat up one of the 100K erase cycles.
With intelligent cache techniques you should be able to get the erase-cycle count for each block very low.
It's *cache*. It's not meant to be moved, and it doesn't prevent you from moving the hard drive. Nor does it prevent you from using an SSD, it just means the performance reasons for using an SSD may get significantly reduced.
Battery backed up (BBU) RAID controllers with volatile RAM cache are very common in the server market because of the huge performance increase of small random writes.
The RAM cache lets the controller cache writes and then send them to the disk in batches while performing write combining so multiple small writes get turned into larger writes reducing the number of disk seeks required to store the data. Also think of the case where your controller has a 512MB cache and you write 200MB to disk. The controller can say OK as soon as it's written to RAM (fraction of a second) where your typical fast disk these days will take 2 seconds.
Without having a battery to back up the volatile RAM cache, you could lose a lot of data if the server lost power, but with it, you go go at least a couple days without losing data.
So now, let's replace that 512MB BBU RAM cache with a 16GB SLC SSD. You won't quite get the burst speed of the BBU RAM controller, but in sustained server loads performance should be a lot better. The SSD will also be able to store a lot more data for reads. If the controller is smart and only uses the SSD for caching random read patterns, you could get close to SSD performance for a lot of workloads but still have 1TB of disk storage.
What if you take it as "cache", one that survives reboots, but where if you really want data persistence you backup it to a more transportable device? Probably will be pretty fast regarding speed (maybe faster than normal ssds, at least regarding bus connection), and having i.e. the most requested files, database slaves for fast queries, swap/temp partitions or even the OS could improve a lot typical pc performance.
Didn't they already try this with their turbocache stuff? I seem to recall the general consensus [anandtech.com] being that it doesn't really offer any remarkable benefits. Regardless of how fast the cache is, eventually you run apps or open files that can't live on it 24x7 and you're going to revert to magnetic HD performance limits. This might improve some battery life and performance for some apps, but its not going to give you the across-the-board speed and battery life boosts that SSDs do. While this would certainly result in a better experience for the average computer user, I feel like its going to be relegated as a middle-ground between HDDs and SDDs, augmenting the low end, but by no means obsoleting the high-end.
I would expect they'd be using some sort of slot, something like this [scan.co.uk]. Motherboard manufacturers aren't exactly going to be thrilled at the idea of putting some yet more expensive components on there, but they might be happy to hook up a small ZIF socket thing like some of them do with CF.
Intel actually had some weird ZIF connected SSD's on there a while ago on preorder, but they appear to have disappeared.
Either way, it's nice to see some hybrid storage stuff which isn't ZFS L2ARC (zpool add tank cache/d
Sooner or later, no moving parts beats moving parts. The magnetic disk makers have done an amazing job so far, but eventually they're going to lose out to solid-state.
No, actually having 4TB of data is way ahead of the curve. The "standard consumer" has maybe 100GB worth of (non-OS) data on a drive, even if the drive is 1TB.
The last few systems I have worked on for 'standard consumers' were all quite upset at being forced into purchasing a 'way too big' 300gb hard drive, simply because any drive under 100gb is both very hard to find, and likely expensive in comparison. 500gb was a waste to them, when they only sync their camera once a month and have office and a couple games installed.
Outside of work where I would be classed as a standard consumer, it would cost me far, far too much to buy enough SSDs to transfer my 4TB of data from my HDDs.
You are not allowed to use "standard consumer" and "4TB of data" in the same sentence:P Careful, they might swoop in and hole punch a warning into your geek card!
Anything >= 2tb is far far above the standard consumer. Even 1tb is far above the average consumer, although 1tb is still falling well within the power user and average gamer groups.
Flash memory is at present growing in capacity much faster than magnetic drives.
If magnetic drives really push the capacity growth that might not hold; magnetic drives have shrunk in size and increased rotational speeds to decrease latency during that time as well. If they just simply give up the performance race and go for vast capacity they could move back to 5 1/4 full height disks. Can you imagine the amount of data you could stick on that surface area with modern technology? I wouldn't be surprised if
Now only if they could start following the server side folks and place an internal USB connector inside and then MS and others could give us the OS on its own usb drive (read only) and we could use the hard drive for updates and programs we could enhance the security as well...
Why a USB connector ? That causes the same problem as making SSD cards use the SATA interface - the serial interface becomes slower than the things it is connected to.
What I would like to see is a set of sockets on the motherboard, mapped into the main memory address space (not PCI), a physical switch on the board to make them read only and software in the BIOS to make them look like a bootable disk.
Four sockets with 16 or 32G in each would give you enough space to store the entire OS. I don't know how Windows would handle it, but in a Unix or Linux based system it would be fairly easy to mount the devices as read only partitions and map them into the filesystem. This would be ideal for a server system, mapping the entire OS into the main memory address space and making it read only.
In fact all the BIOS would need to do is make the first 100M visible as a boot partition, and leave the OS to handle the rest.
Sounds like a good plan. Throw cheap battery backed memory, 4-16Gb onboard to act as a transparent buffer between harddrive(s) and system.
Fast IO is ensured as most operations happen in memory, and dataloss isn't an issue as the memory is battery backed.
RAID cards have done this for ages, but it's becoming real option for desktops as memory price keeps declining.
16Gb might be overkill for most purposes, you could get away with 2 if the system is used only for low-power tasks like surfing and email.
I agree, but why would Intel want to use flash memory for this? RAM is faster, has the capability of a LOT more read/write cycles, and could be backed up by a small battery in the case of short power outages (or maybe a battery big enough to run the hard drive long enough to flush the write buffer, as others have said).
This is essentially a cache, which means it's going to get a lot of reads and writes. Under those circumstances, the flash memory's going to wear out relatively quickly and unless it's easily replaceable it means everyone's going to need to buy new motherboards every year. How could forcing people to replace motherboards annually possibly benefit Intel? Oh, wait...
I read another report (maybe at Anandtech) of the same thing earlier this week. It was a sidenote in a motherboard preview claiming that Intel removed it after it showed no meaningful performance advantage in real use, unlike an SSD.
If the onboard flash is a cache, that means it will be used frequently do it will wear faster.
Won't that mean you're more likely to corrupt your data, even if your HD is still good ?
SLC flash memory, which the article claims Braidwood will use, is an order of magnitude or two more durable (in terms of write cycles) than MLC flash memory, which is what is used in most consumer-level devices like Intel's X-25M SSDs.
Wear-leveling and overprovisioning should ensure a long life for the memory used in a scheme like Braidwood. Intel, generally speaking, knows what they're doing in this area. Now if only I could afford one of their drives...
If the onboard flash is a cache, that means it will be used frequently do it will wear faster.
Won't that mean you're more likely to corrupt your data, even if your HD is still good ?
NAND flash chips are generally guaranteed for at least 100,000 erases per block. As I understand this Braidwood chip, it's a non-volatile ring buffer [wikipedia.org] for data writes. Ring buffers are the easiest thing to wear-level, meaning you can just multiply the cache capacity devoted to writes (let's say 2 GB) by the longevity guarantee to get 200 TB of buffered writes before any failure occurs. And not all blocks on a flash chip fail after the same number of writes; you'll just start to lose ring buffer capacity over
Funny - this very thing was being discussed around 1985 (I think), but using battery-backed RAM as a way to reduce boot time. The thinking was people wouldn't put up with a computer that took 30 seconds to start, and if we didn't have a 2-5 second boot time (equal to a TV), the personal computer would never fly. But since it took from 1985 (80386 chip) to 1995 (Windows 95) for a 32-bit OS to become popular, maybe 25 years is reasonable.
Or not. Man, this industry moves at a snails pace in a lot of areas. Why do we still live with the x86 instruction set. Is "the year of UNIX" here yet?
Anyway, three competitors will emerge:
- Someone will put NAND directly on the drive, and get an instant speed improvement. All the tech sites will rave about it and it will be an instant must-have item.
- Their competitor will figure out a way to put the OS files in NAND, for fast booting, via a utility or firmware. The marketing war begins.
- The third competitor will work with Microsoft or Apple to get OS support for fast boot. Apple will get there first and you'll see a commercial on TV with the Mac guy wondering why the PC guy takes the entire commercial to wake up.
In a single drive system, the cost will be about the same. Doing it on the drive will create an instant performance boost on any machine, and well worth the estimated $10 added cost.
The buffer should obviously be on the hard disk. That way the data on the disk will always be in sync, even if there are writes buffered in the flash cache when the computer loses power. I can't see a good reason to put it on the motherboard instead. Especially as most consumer systems have exactly one HDD.
The article says that the flash buffer could work for "all system io". I can only think of optical disks and flash drives possibilities other than hard disks. But optical disks are interchangeable, so they have to be reread on each use anyway, and could just as well be cached in RAM. And it makes no sense to cache flash drives in flash cache...
Is this the latest FUD? That if a company brings out a successful product that's priced cheaply it'll "erode the market"?
How did the:"market" become so sacred that it must be preserved at all costs by keeping prices high? It's really funny the crap that'll come out of an MBA's mouth. He'll be all for "free markets" until someone comes along with a better product and then he'll start to squeal that the "market" is under siege.
Well hopefully, there will be a BIOS option to disable this hardware in case a failure shows up. Better yet, have them removable much like the old COAST (Cache On A STick) modules of the first gen Pentium days.
First of all, DDR RAM is not cheap (at least, not compared to NAND RAM). It costs significantly more per gigabyte than even the most expensive of Intel's offerings for SSD's. While it should provide more theoretical throughput than any SSD, benchmarks at various places (http://techreport.com/articles.x/16255/1) haven't shown that to be significant yet, at least from the end user perspective (some synthetic benchmarks show that the RAM based disks can be faster than SSD's, but translating that to real world usage scenarios by consumers doesn't quite show any tangible benefits).
DDR RAM uses up a very large amount of power per stick compared to SSD's do. I remember seeing the power consumption of one of the DDR2 based "volatile hard drives", and it was higher than spinning drives (at least at idle), and wasn't particularly faster than the best of intel's SSD's.
So sounds like DDR RAM on board is expensive, power hungry, and doesn't provide that much of a tangible benefit to consumers. Tell me again why it's a good idea?
Well, obviously the volatile drives aren't much faster than Intel's SSDs. Most SSDs are already starting to bump against the upper limit of what you can get out of SATAII when doing sequential reads.
The first ones I saw were for the PCI-slot and that one is limited to 133 MB/s and 266 MB/s for 64 bit PCI, both of which are lower rates than SATAII.
PCI Express [wikipedia.org] of course starts at 250 MB/s per lane and tops out at 1 GB/s per lane for the latest version. Compare that to DDR3 [wikipedia.org] which peaks at 12.8 GB/s per channel
Exactly. I already have a disk cache. This solution is redundant. Also, this solution doesn't get me away from the mechanical spinning noisy hot slow thing which fails too often.
I'd answered yes, but one doesn't control the fsync behavior of every application running on his/her system and the OS/file system can take a lot of time (even tens of seconds or more) before deciding to commit changes to the hard disk. Furthermore, a fsync may take seconds to complete and disaster can strike at any time.
There was quite a commotion about those matters when somebody filed a data loss bug [launchpad.net] against the new Linux ext4 file system in January 2009. It turned out that ext3 commits changes at least
It's more the case of hedging characteristics against each other.
1. SSDs handle random I/O extremely well compared to traditional harddisks.
2. Braidwood is essentially a small, cheap, 8-16GB flash based cache.
3. If Braidwood is transparent to the OS, it will have a hard time guessing what to put in the cache, because a lot of the I/O on a desktop/laptop is random, but the issue with caching the non-random part is that most OSs do caching themselves for frequently accessed parts of the disk. This means t
I'm sure that would come as a great surprise to anyone who ever implemented a virtual memory system.
-jcr
You're both right.
The problem here is that "random I/O" can have at least two subtly different meanings. In the very old days they talked about random I/O as opposed to sequential (ie, tape) I/O. In that sense, yes, random I/O is often extremely cacheable, as you say. That's why virtual memory works, as system files, drivers, commonly-used applications, and so forth are accessed much more often than other daa.
"Random I/O" can also refer to I/O that does not follow any real pattern - ie, a 50GB database in which all records are accessed about equally as often. This kind of I/O is not really cacheable, practically speaking. Unless you can cache the entire thing.
What's the correct terminology for the second kind of random I/O? Random I/O with very low locality?
Not so sure (Score:5, Interesting)
Re:Not so sure (Score:5, Insightful)
I can't take the flash to the next PC as i can do with the SSD.
Not really a big deal; if it becomes commonplace, most PCs will eventually have it (or something like it) as standard anyway and you won't be bothered about it.
Parent
Re:Not so sure (Score:5, Interesting)
"(...)if it becomes commonplace, most PCs will eventually have it (...)"
Which opens an interesting hole. That flash on motherboard will hold some data to speed up system startup. That means first n opened files. With that flash big enough it will also hold quite a lot of user documents. Unless documents can be marked as "not to be cached" it will add extra headache when getting rid of old systems. We have it already with 419ers buying old PCs and smartphones, gangs dumpsterdiving, etc.
Also try to explain to customers that they will need to erase flash they cannot see in system (and will most probably not even know about it!) or destroy the chip before throwing away old system. With HDDs it's quite hard and those are big, visible and has been around for ages.
Parent
Re: (Score:3, Insightful)
Re:Not so sure (Score:5, Interesting)
Seems to me that this article is a thinly-veiled marketing trick. Somebody publishes a paper, "Will Intel product A beat Intel product B?", and presto, we've got buzz about product A which doesn't even come close to competing with product B (which is a market leader, dontchaknow), and increased buzz about product B. Then, people chime in with their arguments and counterarguments about which product is better... and Intel wins no matter what. Both product lines are probably going to succeed independently of one another.
That said, Braidwood sounds awesome to me, especially because my servers talk to a storage box over NFS, and fast onboard cache sounds great to me. But, I want fast local storage too, and 16GB is nothing, so I want large-capacity SSD drives. I really don't see these as competing products. This is just a slashvertizement. Move along, folks.
Parent
Re:Not so sure (Score:5, Insightful)
Whoever defined parent as troll must be weird.
That said - I'm more worrying about the consideration about exhausted flash on the motherboard. Have all avenues actually been considered here, or is that a built-in best before date that new motherboards will have?
Parent
Re: (Score:3, Insightful)
TFA says it'll be used for an I/O cache, so I supsect it'll get hit slightly more often than that.
Re: (Score:3, Insightful)
Actually if it's a cache the size could just reduce as the flash wears out.
Re:Not so sure (Score:4, Interesting)
Actually not. It is going to store quite permanently only some files used to speed up system processing. There is not going to be any journals, and the filesystem will be highly optimised for this kind of usage. That is from press release I read somewhere. So even MLC will last long time as writes will be very limited. Only issue is that to drive costs down controller is also going to be scaled down so no great magic as with SSDs. So if somebody hacks that flash to use as HDD it will wear quite badly and quickly.
Parent
Re: (Score:3, Insightful)
With intelligent cache techniques you should be able to get the erase-cycle count for each block very low.
Re:Not so sure (Score:5, Informative)
Parent
Re:Not so sure (Score:5, Interesting)
Which brings up an interesting design thought:
Battery backed up (BBU) RAID controllers with volatile RAM cache are very common in the server market because of the huge performance increase of small random writes.
The RAM cache lets the controller cache writes and then send them to the disk in batches while performing write combining so multiple small writes get turned into larger writes reducing the number of disk seeks required to store the data. Also think of the case where your controller has a 512MB cache and you write 200MB to disk. The controller can say OK as soon as it's written to RAM (fraction of a second) where your typical fast disk these days will take 2 seconds.
Without having a battery to back up the volatile RAM cache, you could lose a lot of data if the server lost power, but with it, you go go at least a couple days without losing data.
So now, let's replace that 512MB BBU RAM cache with a 16GB SLC SSD. You won't quite get the burst speed of the BBU RAM controller, but in sustained server loads performance should be a lot better. The SSD will also be able to store a lot more data for reads. If the controller is smart and only uses the SSD for caching random read patterns, you could get close to SSD performance for a lot of workloads but still have 1TB of disk storage.
Parent
Re: (Score:3, Interesting)
Re:Not so sure (Score:5, Insightful)
Parent
Re: (Score:3, Interesting)
Re: (Score:3, Insightful)
I would expect they'd be using some sort of slot, something like this [scan.co.uk]. Motherboard manufacturers aren't exactly going to be thrilled at the idea of putting some yet more expensive components on there, but they might be happy to hook up a small ZIF socket thing like some of them do with CF.
Intel actually had some weird ZIF connected SSD's on there a while ago on preorder, but they appear to have disappeared.
Either way, it's nice to see some hybrid storage stuff which isn't ZFS L2ARC (zpool add tank cache /d
The writing's on the wall. (Score:5, Insightful)
Sooner or later, no moving parts beats moving parts. The magnetic disk makers have done an amazing job so far, but eventually they're going to lose out to solid-state.
-jcr
Re:The writing's on the wall. (Score:5, Insightful)
Just goes to show how warped a professional's perspective really is. Standard consumer with 4TB of data? Really?
Parent
Re: (Score:3, Insightful)
The RIAA and MPAA would have you believe that each man, woman, and child has downloaded at least that much illegal movies and music.
Re: (Score:3, Insightful)
Re:The writing's on the wall. (Score:5, Insightful)
Parent
Re: (Score:3, Informative)
Re:The writing's on the wall. (Score:5, Interesting)
Capacity is still an issue though.
Not really for most people.
The last few systems I have worked on for 'standard consumers' were all quite upset at being forced into purchasing a 'way too big' 300gb hard drive, simply because any drive under 100gb is both very hard to find, and likely expensive in comparison. 500gb was a waste to them, when they only sync their camera once a month and have office and a couple games installed.
Outside of work where I would be classed as a standard consumer, it would cost me far, far too much to buy enough SSDs to transfer my 4TB of data from my HDDs.
You are not allowed to use "standard consumer" and "4TB of data" in the same sentence :P
Careful, they might swoop in and hole punch a warning into your geek card!
Anything >= 2tb is far far above the standard consumer. Even 1tb is far above the average consumer, although 1tb is still falling well within the power user and average gamer groups.
Parent
Re: (Score:3, Interesting)
Flash memory is at present growing in capacity much faster than magnetic drives.
If magnetic drives really push the capacity growth that might not hold; magnetic drives have shrunk in size and increased rotational speeds to decrease latency during that time as well. If they just simply give up the performance race and go for vast capacity they could move back to 5 1/4 full height disks. Can you imagine the amount of data you could stick on that surface area with modern technology? I wouldn't be surprised if
Ohh - maybe they could take it to the next step... (Score:4, Interesting)
Now only if they could start following the server side folks and place an internal USB connector inside and then MS and others could give us the OS on its own usb drive (read only) and we could use the hard drive for updates and programs we could enhance the security as well...
Re:Ohh - maybe they could take it to the next step (Score:5, Interesting)
Why a USB connector ? That causes the same problem as making SSD cards use the SATA interface - the serial interface becomes slower than the things it is connected to.
What I would like to see is a set of sockets on the motherboard, mapped into the main memory address space (not PCI), a physical switch on the board to make them read only and software in the BIOS to make them look like a bootable disk.
Four sockets with 16 or 32G in each would give you enough space to store the entire OS. I don't know how Windows would handle it, but in a Unix or Linux based system it would be fairly easy to mount the devices as read only partitions and map them into the filesystem. This would be ideal for a server system, mapping the entire OS into the main memory address space and making it read only.
In fact all the BIOS would need to do is make the first 100M visible as a boot partition, and leave the OS to handle the rest.
Parent
So when I drop my laptop, the NAND saves my HDD? (Score:5, Funny)
HW buffer for drives (Score:3, Interesting)
Fast IO is ensured as most operations happen in memory, and dataloss isn't an issue as the memory is battery backed.
RAID cards have done this for ages, but it's becoming real option for desktops as memory price keeps declining.
16Gb might be overkill for most purposes, you could get away with 2 if the system is used only for low-power tasks like surfing and email.
Re:HW buffer for drives (Score:4, Insightful)
I agree, but why would Intel want to use flash memory for this? RAM is faster, has the capability of a LOT more read/write cycles, and could be backed up by a small battery in the case of short power outages (or maybe a battery big enough to run the hard drive long enough to flush the write buffer, as others have said).
This is essentially a cache, which means it's going to get a lot of reads and writes. Under those circumstances, the flash memory's going to wear out relatively quickly and unless it's easily replaceable it means everyone's going to need to buy new motherboards every year. How could forcing people to replace motherboards annually possibly benefit Intel? Oh, wait...
Parent
Is Braidwood already canceled? (Score:5, Informative)
There have also been rumors, however, that Braidwood has been canceled, at least in the near term:
http://www.dvhardware.net/article37368.html [dvhardware.net]
Re:Is Braidwood already canceled? (Score:5, Informative)
There have also been rumors, however, that Braidwood has been canceled, at least in the near term:
http://www.dvhardware.net/article37368.html [dvhardware.net]
I read another report (maybe at Anandtech) of the same thing earlier this week. It was a sidenote in a motherboard preview claiming that Intel removed it after it showed no meaningful performance advantage in real use, unlike an SSD.
Parent
Re: (Score:3, Informative)
No surprise: Isn't this basically what ReadyBoost [wikipedia.org] does?
How about the reliability ? (Score:3, Insightful)
Re:How about the reliability ? (Score:5, Informative)
SLC flash memory, which the article claims Braidwood will use, is an order of magnitude or two more durable (in terms of write cycles) than MLC flash memory, which is what is used in most consumer-level devices like Intel's X-25M SSDs.
Wear-leveling and overprovisioning should ensure a long life for the memory used in a scheme like Braidwood. Intel, generally speaking, knows what they're doing in this area. Now if only I could afford one of their drives...
Parent
Reliability: 100 TB (Score:3, Informative)
If the onboard flash is a cache, that means it will be used frequently do it will wear faster. Won't that mean you're more likely to corrupt your data, even if your HD is still good ?
NAND flash chips are generally guaranteed for at least 100,000 erases per block. As I understand this Braidwood chip, it's a non-volatile ring buffer [wikipedia.org] for data writes. Ring buffers are the easiest thing to wear-level, meaning you can just multiply the cache capacity devoted to writes (let's say 2 GB) by the longevity guarantee to get 200 TB of buffered writes before any failure occurs. And not all blocks on a flash chip fail after the same number of writes; you'll just start to lose ring buffer capacity over
On-Drive NAND also quite likely (Score:4, Interesting)
Funny - this very thing was being discussed around 1985 (I think), but using battery-backed RAM as a way to reduce boot time. The thinking was people wouldn't put up with a computer that took 30 seconds to start, and if we didn't have a 2-5 second boot time (equal to a TV), the personal computer would never fly. But since it took from 1985 (80386 chip) to 1995 (Windows 95) for a 32-bit OS to become popular, maybe 25 years is reasonable.
Or not. Man, this industry moves at a snails pace in a lot of areas. Why do we still live with the x86 instruction set. Is "the year of UNIX" here yet?
Anyway, three competitors will emerge:
- Someone will put NAND directly on the drive, and get an instant speed improvement. All the tech sites will rave about it and it will be an instant must-have item.
- Their competitor will figure out a way to put the OS files in NAND, for fast booting, via a utility or firmware. The marketing war begins.
- The third competitor will work with Microsoft or Apple to get OS support for fast boot. Apple will get there first and you'll see a commercial on TV with the Mac guy wondering why the PC guy takes the entire commercial to wake up.
In a single drive system, the cost will be about the same. Doing it on the drive will create an instant performance boost on any machine, and well worth the estimated $10 added cost.
The flash buffer should be on the HDD (Score:5, Interesting)
The buffer should obviously be on the hard disk. That way the data on the disk will always be in sync, even if there are writes buffered in the flash cache when the computer loses power. I can't see a good reason to put it on the motherboard instead. Especially as most consumer systems have exactly one HDD.
The article says that the flash buffer could work for "all system io". I can only think of optical disks and flash drives possibilities other than hard disks. But optical disks are interchangeable, so they have to be reread on each use anyway, and could just as well be cached in RAM. And it makes no sense to cache flash drives in flash cache...
What nonsense (Score:5, Insightful)
Is this the latest FUD? That if a company brings out a successful product that's priced cheaply it'll "erode the market"?
How did the :"market" become so sacred that it must be preserved at all costs by keeping prices high? It's really funny the crap that'll come out of an MBA's mouth. He'll be all for "free markets" until someone comes along with a better product and then he'll start to squeal that the "market" is under siege.
Good for Intel.
Re:why flash? (Score:5, Informative)
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Re:why flash? (Score:4, Insightful)
Well hopefully, there will be a BIOS option to disable this hardware in case a failure shows up. Better yet, have them removable much like the old COAST (Cache On A STick) modules of the first gen Pentium days.
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Re: (Score:3, Insightful)
Re:why flash? (Score:4, Informative)
First of all, DDR RAM is not cheap (at least, not compared to NAND RAM). It costs significantly more per gigabyte than even the most expensive of Intel's offerings for SSD's. While it should provide more theoretical throughput than any SSD, benchmarks at various places (http://techreport.com/articles.x/16255/1) haven't shown that to be significant yet, at least from the end user perspective (some synthetic benchmarks show that the RAM based disks can be faster than SSD's, but translating that to real world usage scenarios by consumers doesn't quite show any tangible benefits).
DDR RAM uses up a very large amount of power per stick compared to SSD's do. I remember seeing the power consumption of one of the DDR2 based "volatile hard drives", and it was higher than spinning drives (at least at idle), and wasn't particularly faster than the best of intel's SSD's.
So sounds like DDR RAM on board is expensive, power hungry, and doesn't provide that much of a tangible benefit to consumers. Tell me again why it's a good idea?
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Re: (Score:3, Interesting)
Well, obviously the volatile drives aren't much faster than Intel's SSDs. Most SSDs are already starting to bump against the upper limit of what you can get out of SATAII when doing sequential reads.
The first ones I saw were for the PCI-slot and that one is limited to 133 MB/s and 266 MB/s for 64 bit PCI, both of which are lower rates than SATAII.
PCI Express [wikipedia.org] of course starts at 250 MB/s per lane and tops out at 1 GB/s per lane for the latest version. Compare that to DDR3 [wikipedia.org] which peaks at 12.8 GB/s per channel
Re: (Score:3, Insightful)
Re:why flash? (Score:5, Funny)
Stop using a typewriter to post on Slashdot.
Signed, everyone.
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Re: (Score:3, Insightful)
I'd answered yes, but one doesn't control the fsync behavior of every application running on his/her system and the OS/file system can take a lot of time (even tens of seconds or more) before deciding to commit changes to the hard disk. Furthermore, a fsync may take seconds to complete and disaster can strike at any time.
There was quite a commotion about those matters when somebody filed a data loss bug [launchpad.net] against the new Linux ext4 file system in January 2009. It turned out that ext3 commits changes at least
Re:Bullshit (Score:5, Insightful)
Random I/O is essentially uncacheable.
I'm sure that would come as a great surprise to anyone who ever implemented a virtual memory system.
-jcr
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Re: (Score:3, Insightful)
Random I/O is essentially uncacheable.
I'm sure that would come as a great surprise to anyone who ever implemented a virtual memory system.
His flaw lies in assuming- or implying- that most I/O *is* random.
Re: (Score:3, Insightful)
1. SSDs handle random I/O extremely well compared to traditional harddisks.
2. Braidwood is essentially a small, cheap, 8-16GB flash based cache.
3. If Braidwood is transparent to the OS, it will have a hard time guessing what to put in the cache, because a lot of the I/O on a desktop/laptop is random, but the issue with caching the non-random part is that most OSs do caching themselves for frequently accessed parts of the disk. This means t
Re:Bullshit (Score:5, Insightful)
Random I/O is essentially uncacheable.
I'm sure that would come as a great surprise to anyone who ever implemented a virtual memory system.
-jcr
You're both right.
The problem here is that "random I/O" can have at least two subtly different meanings. In the very old days they talked about random I/O as opposed to sequential (ie, tape) I/O. In that sense, yes, random I/O is often extremely cacheable, as you say. That's why virtual memory works, as system files, drivers, commonly-used applications, and so forth are accessed much more often than other daa.
"Random I/O" can also refer to I/O that does not follow any real pattern - ie, a 50GB database in which all records are accessed about equally as often. This kind of I/O is not really cacheable, practically speaking. Unless you can cache the entire thing.
What's the correct terminology for the second kind of random I/O? Random I/O with very low locality?
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