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Flash Drives in Future Apple Laptops?

Posted by CowboyNeal on from the shock-proof-storage dept.

danscript writes "Samsung hopes that falling prices for flash-memory chips will mean solid-state memory can eventually replace hard-disk drives in Apple PowerBooks and iBooks as well as other devices, Macworld UK is reporting. The benefits? - silent; less power; reliable and faster."

33 of 353 comments (clear)

  1. Flash by Zlib+pt · · Score: 5, Funny

    "I'm sorry sir. You can only install OSX 10 times. Then you ran out of read/write operations"

    1. Re:Flash by FidelCatsro · · Score: 5, Interesting

      That's not really a worry any more , modern flash memory has a substantially greater number of read/ write cycles.
      IIRC the numbers are good enough that they would probably live as long if not longer than your average laptop HDDs .

      --
      The only things certain in war are Propaganda and Death. You can never be sure which is which though
    2. Re:Flash by advocate_one · · Score: 4, Funny
      IIRC the numbers are good enough that they would probably live as long if not longer than your average laptop HDDs.

      the only people who might possibly run into the write limit would be Gentoo users...

      --
      Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
    3. Re:Flash by WonderSnatch · · Score: 3, Informative

      I'm guessing these drives would have a sort of "wear leveling" just like they have in most compact flash cards.

      The wear leveling works by keeping a table of what physical flash is mapped to what address. The trouble comes when power is yanked whilst the table is in the middle of an update.

      Brett

    4. Re:Flash by MaynardJanKeymeulen · · Score: 5, Interesting
      Thumb drives are slower, let's do a test:
      [root@pentie4 /]# hdparm -t /dev/sde2

      /dev/sde1:
      Timing buffered disk reads: 78 MB in 3.04 seconds = 25.69 MB/sec
      [root@pentie4 /]# hdparm -t /dev/sde1

      /dev/sdc1:
      Timing buffered disk reads: 36 MB in 7.43 seconds = 4.84 MB/sec
      with sde my USB2 harddisk and sdc a USB2 thumbdrive.
      --
      "The day Microsoft makes a product that doesn't suck is the day they make a vacuum cleaner."
    5. Re:Flash by WonderSnatch · · Score: 3, Informative

      In fact, here's a white paper from Sandisk.

      Brett

    6. Re:Flash by alienw · · Score: 5, Informative

      Not true. Modern Flash cards have wear leveling built into the hardware. The address the computer sees is actually the logical address that the controller translates to a hardware-specific address. The controller automatically adjusts addresses to spread out the writes and to detect and remap bad blocks (this should occur without loss of data, since blocks only go bad when you write to them).

    7. Re:Flash by Just+Some+Guy · · Score: 5, Insightful
      Thumb drives are slower

      ...at sequential reading. Wanna run the same test with bonnie++ or another benchmark that slams the drive with random accesses? I'll bet the near-zero seek penalty on solid state media makes up for quite a bit of its currently mediocre sequential access.

      Imagine a database where you're writing millions of tiny blocks of data all over the place. Within reason, fast seeks are about as important as fast IO.

      --
      Dewey, what part of this looks like authorities should be involved?
    8. Re:Flash by Hal_Porter · · Score: 5, Informative
      Here's how it works on NOR flash.

      The flash is broken up into Erase Units, which as the name suggests is the smallest block you can erase at any one time. IDE hard disks have a small fixed sectorsize of 512 bytes, smaller than one EU.

      Imagine a 12KB flash with a 2KB Erase Unit and 6 units. One of these is bad - this can seen by the absence of a metadata signature for example.

      You could use this as an IDE disk with 6KB capacity, since some of the erase units needs to be spare at all times.

      Each EU can hold 3 IDE sectors, some metadata including the signature, and then 3 integers saying which logical block the physical block holds.

      The EU starts off erased, all ones. Let's write a fileystem,
      EU 1
      lookup table contains (1,2,3)
      IDE sector 1
      IDE sector 2
      IDE sector 3
      EU 2
      lookup table contains (4,5,6)
      IDE sector 4
      IDE sector 5
      IDE sector 6
      EU 3
      lookup table contains (7,8,9)
      IDE sector 7
      IDE sector 8
      IDE sector 9
      EU 4
      lookup table contains (-1,-1,-1)
      spare - every bit in this EU is one
      EU 5
      lookup table contains (-1,-1,-1)
      spare - every bit in this EU is one
      EU 6
      bad
      Now imagine we need to update sector 1. We can use one of the spare blocks to store the data. The old copy can be left, but marked as unused by setting its lookup table entry to 0 - programming all the remaining bits.
      EU 1
      lookup table contains (0,2,3)
      IDE sector 1 (obsolete data)
      IDE sector 2
      IDE sector 3
      ... no change, damn lameness filter
      EU 4
      lookup table contains (1,-1,-1)
      IDE sector 1 (latest copy)
      spare (all ones)
      spare (all ones)
      ... no change
      Now imagine that you need to write the next two blocks, 2 and 3. That way all the blocks in the first EU will be obsolete, and you can erase it.
      EU 1
      lookup table contains (-1,-1,-1)
      spare (all ones)
      spare (all ones)
      spare (all ones)
      ... no change
      EU 4
      lookup table contains (1,2,3)
      IDE sector 1
      IDE sector 2
      IDE sector 3
      ... no change
      If you're not lucky enough to get all the blocks written at any one time, you need to compact by copying the block with the most obsolete blocks into one of the spare EU's. Obvously you can skip the obsolete blocks - you just copy the ones that are used and mark the rest as spare.

      So far I've talked about one lookup table, the one in the flash which gives you the logical block which each physical block contains. This is the inverse of the lookup table you want for reading an arbitrary block, but this inverseness gives it the useful property that it only needs to be updated only once per erase cycle - some of the bits in an entry are programmed when the block is written, and the rest are programmed when the data becomes obsolete.

      If you want to read logical block N, it's useful to have another lookup table which gives you the mapping logical block to physical block. This will need to be updated a lot - once for each write of a block. But it can be generated from the lookup table in the flash at insertion time, and kept in Ram.

      There are some corner cases obviously - like the bad bits in the metadata area or whole EU's going bad, but there's usually a fair bit of space in an EU for metadata, and a reasonable number of spare EUs. Plus, if the flash has always been used like this, the bits should all wear out at the same time, which is obviously not something you can work around. But the trick to avoiding the problem you mention is to store an _inverted_ lookup table on the flash.
      --
      echo -e 'global _start\n _start:\n mov eax, 2\n int 80h\n jmp _start' > a.asm; nasm a.asm -f elf; ld a.o -o a;
  2. Too Bad pn Junctions cost more than magnets by Metaphorically · · Score: 5, Interesting

    I remember talking to a guy at Radio Shack about flash-based drives and how this was going to be the new option back in 1992. I think they were calling it a "hard card." Looking back, it was probably the same thing as PCMCIA Flash drive. That's the precursor to Compact Flash cards for you young'uns.

    It wasn't new then and it isn't new now. Is it time? Sure. It's long overdue and I'd love to see solid state drives suddenly become financially feasable.

    I doubt it's going to happen though because it seems like the cost of the magnetic materials used in disc platters will always be low and a solid state memory cell (flash, ram, eeprom, whatever) takes a couple transistors. The price of both drops, but hard drive price per GB (or MB, TB, whatever) always drops faster because of the lower transistor count.

    --
    more of the same on Twitter.
    1. Re:Too Bad pn Junctions cost more than magnets by yttrstein · · Score: 3, Insightful

      SCSI, SATA and ATA controllers found on each and every hard drive made take quite a bit more than a couple transistors.

    2. Re:Too Bad pn Junctions cost more than magnets by KD5YPT · · Score: 5, Informative

      The point he's making is that the controller on harddrive have a relatively fix amount of transistor, regardless of the harddrive's space. Flash mem, however, needs a set of transistor for every bit of data it stores.

      --
      In US, you can easily buy enough major firearms to wipe out your neighbourhood but a few little fireworks are banned.
    3. Re:Too Bad pn Junctions cost more than magnets by FidelCatsro · · Score: 4, Interesting

      Sometimes good tech just takes years to catch on and neigh on useless legacy crap takes forever to die off. Just look at the fact that FDDs are still clinging on tooth and nail in the PC world.
      LPT ports are still used for printers , serial ports still come as standard on most motherboards .

      I think the principle advantage is in the power consumption for laptops, Batteries are really expensive , if you use your Laptop on the road a lot then it has two principle advantages , lower power consumption and its far far more robust to damage due to things like dropping .
      In this field of the ultra compact laptops i would say that the Power consumption and durability will outweigh the per GB cost .
      If the write/erase cycles are now within the realms that samsung is considering offering these drives for commercial sale then i would defiantly want one in my laptop , i could easily cope with 15GB on a portable device for work.

      --
      The only things certain in war are Propaganda and Death. You can never be sure which is which though
    4. Re:Too Bad pn Junctions cost more than magnets by pedantic+bore · · Score: 4, Informative
      No, the "hard card" was a self-contained hard drive that could be installed, like a peripheral card, directly into a mobo slot. Nice idea for old cases that didn't have expansion drive bays. Saw lots in stores, but never saw many in actual computers...

      On the other hand, you might be thinking of bubble memory... which was going to be the next big thing in the early 80's. Still waiting on that one.

      --
      Am I part of the core demographic for Swedish Fish?
    5. Re:Too Bad pn Junctions cost more than magnets by shine-shine · · Score: 3, Insightful
      The price of both drops, but hard drive price per GB (or MB, TB, whatever) always drops faster

      This isn't to say that solid state drives won't become popular. If I can get a 80GB solid state drive for the price of a standard 400GB HD, I'd go for it. I think this is exactly what'll happen. As capacity grows, it becomes less and less important for people to have the largest HD on the market. Sure, many people have the need for large drives (video editing, pr0n, etc.), but most can do just fine with tenth the size of a modern HD. Especially when it comes to laptops.

    6. Re:Too Bad pn Junctions cost more than magnets by pete-classic · · Score: 5, Informative

      Hard cards were the original IDE drives. Before hard cards you had to have an actual disk controller plugged into your bus, then cabled to the drive. IDE, in it's original implementation, was just an ISA slot re-configured as a pin header connector with some unneeded pins (such as all the IRQs except for 14 or 15) removed.

      With all the advances that IDE has taken, it is still a simple interface, not a disk controller.

      Hard cards didn't last long, but they're an important mutation in the evolution of the modern PC.

      -Peter

  3. faster writes? by nblender · · Score: 5, Informative

    They must be talking about some other kind of flash than anything I've used... I routinely rewrite 128MB-512MB CF cards for an embedded product and it's nowhere near the speed of a laptop disk. Maybe they're thinking some sort of RAM cache.

    1. Re:faster writes? by Metaphorically · · Score: 4, Informative

      Write speed for flash is slower than read speed for flash, but making a direct comparison like that can be tricky because of differences in the technology.

      Flash memory has to be erased before it can be written and has an inherent minimum erase block size. This has made designers put some write buffering in the card (at least in the older PC Card devices, which afaik are just bigger versions of CF cards). That write buffering is one layer of caching, then there can be additional layers of read and write caching in the driver.

      Generally those caches improve normal use of the device, but in cases like yours you blow right through all those caches since you're rewriting the whole card.

      btw, that caching is why you have to tell Windows to eject the device before you pull it out. Your write might not have actually finished even though you can do other things to the drive in Explorer.

      --
      more of the same on Twitter.
  4. Reliable? Don't think so. by Anonymous Coward · · Score: 4, Insightful

    Show me a flash drive that survives a couple of million write cycles, and I might consider using a flash drive instead of a normal hard drive.

    1. Re:Reliable? Don't think so. by kesuki · · Score: 4, Informative

      I've even read articles

      What are you doing on /. then?

      but seriously, prior to wear leveling (ie: antique 32MB cards, early controllers/drivers etc..) this was a valid statement, however cards back then only had 10k or fewer rewrite cycles. the rewrite cycles have gone up 10 fold, and wear leveling makes sure that data that is 'rewritten' is actually written on a portion of the disc that was previously determined to be a low write, freely alloctabale block, and they always keep spare low write sectors available. it's even possible for a hard drive such as this to Warn users of impending drive failure. BTW when a block on a 'flash' based drive 'fails' it falls back into read only mode. only the data it attempted to write must now be written somewhere else.

      Also, to get back on track the MTBF for most platter based hard drives is something along the lines of 50,0000 hours for a really top notch drive, reading/writing the entire disc will on average take ~2 hours, requardless of capacity, because that's how long it takes the data heads to travel the entire platter surface area... so statistically, you have 25k write cycles before failure on a conventional hard drive. so how is that inferior to flash memory? and remember, this is APPLE Macintosh running of a FreeBSD derived kernel. put the right amount of ram in the laptop, and it will _never_ use swap space.

      --
      https://www.gnu.org/philosophy/free-sw.html
  5. extra bonus by justforaday · · Score: 3, Funny

    The extra bonus: Apple gets to sell you a new one after 1,000 or so boots... : p

    --
    I'll turn into a supernova and burn up everything. Well I'll turn into a black little hole and you'll turn into string.
    1. Re:extra bonus by rokzy · · Score: 4, Funny

      who is booting a Mac 1000 times?

      you're obviously a Windows user.

  6. Silence is golden, but is flash big enough? by G4from128k · · Score: 3, Interesting

    We know that the black turtle-necked one hates noisy machines and I agree with him. I configured an old Powerbook 190cs to boot from a CF card in the PCMCIA slot -- wonderfully silent and much faster than booting from the HD. Of course on that old machine, the OS, a couple of applications, and some files fit nicely in only a 4 MB flash memory. In contrast, OSX, modern apps, and files will need 1024 times that space (4 GB) at a minimum and tens of GB if the person has even a modest collection of media files.

    I can only hope that Samsung's technology roadmap (16 GB by 2006, 100 GB by 2008) is correct although I wonder how HD technology will have evolved over those same years.

    --
    Two wrongs don't make a right, but three lefts do.
  7. 18Gb prototype info here: by Idou · · Score: 4, Informative

    http://www.physorg.com/news4220.html

    --
    Sdelat' Ameriku velikoy Snova!
  8. Re:Flash still has lots of room to grow by Anita+Coney · · Score: 4, Insightful

    Not every one is concerned about massive drive sizes. There are plenty of people who would choose the battery saving advantages of flash drives in their laptops.

    I'm of the opinion that laptops should be as small and energy efficent as possible. I just don't get the point of using them desktop replacements. If you want something as huge and powerful as desktop, buy a friggin' desktop. If you want something portable, buy something portable.

    I mean, what's the point of a "portable" computer if you have to plug it in all the time?!

    --
    If someone says he and his monkey have nothing to hide, they almost certainly do.
  9. Well, of course he wants it to happen by intmainvoid · · Score: 3, Insightful
    The most recent IDC data ranks Samsung as the world's number one producer of flash chips


    So of course "Hwang Chang-Gyu, president and CEO of Samsung's semiconductor business" wants his company's technology to take over from hard drives. That's very different to Apple saying it will happen.

    --
    Drag n' Drop DVD Recommendations
  10. Two drives: one flash, one magnetic by AdamInParadise · · Score: 5, Interesting

    I've been thinking about this for a long time. What about using a flash drive for the important stuff (OS+user docs) and a hard drive for the unimportant stuff (divxes, CD backups, you name it)? Basically, the hard drive would be powered down most of the time, bringing down noise and heat, therefore driving up the reliability of the whole system. That's certainly possible with every kind of computer out there, but it would be better with specific OS support. For example, the OS could transparently copy your data back and forth between both drives, like the iPod does (with RAM instead of Flash).

    Regards

    --
    Nobox: Only simple products.
  11. Flash or SFF drives... by Wdomburg · · Score: 3, Interesting

    I don't doubt flash may make some headway in the ultraportable market, but the advances in microdrive technology promise escalating capacity with reduced power consumption. Toshiba's already announced an 80GB drive in a 1.8" form factor, drawing around 1.4W and Hitachi has been talking up plans for a 20GB drive in a 1" form factor.

  12. whats so new about this ? by Dolphinzilla · · Score: 3, Informative

    http://www.m-systems.com/content/Products/product. asp?pid=34

    M-Systems has been providing fast FLASH based 2.5" laptop drives in the 1 GB to 128 GB range for a while - while they are god awful expensive, they do work very well and I have used them in several mission critical applications. My hope is that Samsung can get the price point down by an order of magnitude (or two)

  13. the number of writes is 10,000... by Anonymous Coward · · Score: 5, Informative

    It used to be higher, (up to 100,000), but new MLC flash has lower numbers. Note that the 1,000,000 numbers you read is low-density NOR flash, not the NAND flash a hard drive would be made of.

    You must wear level, so the real life of the drive is basically 10,000*num sectors writes. A sector is 128KB or so, depending on the flash type.

    This seems like a lot until you realize that often you write sectors over and over. Also, due to the large sector/page size of flash, you end up doing multiple writes when you think you are doing a single one. For example, if you write to a file in 4 chunks, 32K at a time, it uses up 4 of your writes. It might be possible to remove this with intelligent caching, but you're gonna need a lot of RAM for the caching.

    Honestly, this is just an idea that isn't ready yet. Flash is too slow to write right now. The life is decent. Reads work well.

    1. Re:the number of writes is 10,000... by Shanep · · Score: 3, Interesting
      due to the large sector/page size of flash, you end up doing multiple writes when you think you are doing a single one. For example, if you write to a file in 4 chunks, 32K at a time, it uses up 4 of your writes. It might be possible to remove this with intelligent caching, but you're gonna need a lot of RAM for the caching.

      That is interesting. I know modern CF cards employ wear levelling within the cards themselves, but I was previously leaning on BSD's soft-updates and noatime to prolong to life of the CF cards in a few servers and firewalls. Maybe some slices should also have FFS file systems with a 128kb block size to limit any block to no more than one file. I'm off to see if FFS in OpenBSD can use a block size of 128kb. Assuming this would actually cause 128kb block sized writes?

      Honestly, this is just an idea that isn't ready yet. Flash is too slow to write right now. The life is decent. Reads work well.

      Yes I must say that I find the high speed flash cards I use, which are directly plugged into my motherboards IDE controllers via passive IDE-CF converters (no electronics, just different connectors at either ends of the converters), are slow to write.

      I have Lexar Pro series 80X CF's and San Disk Ultra II CF's. The Lexar's are WAY faster than the San Disk's BTW. But still they're pretty slow. I use them in Sun Ultra 10's and 5's, which have really slow IDE interfaces, but the CF's are slower than these and are also slow in various PC's I've tried them in.


      # dd bs=64k count=1024 if=/dev/zero of=/tmp/64MB.bin
      1024+0 records in
      1024+0 records out
      67108864 bytes transferred in 54.374 secs (1,234,192 bytes/sec)

      # dd bs=128k count=512 if=/dev/zero of=/tmp/64MB.bin
      512+0 records in
      512+0 records out
      67108864 bytes transferred in 54.322 secs (1,235,385 bytes/sec)

      # dd bs=64k count=1024 if=/dev/zero of=/var/log/pf/64MB.bin
      1024+0 records in
      1024+0 records out
      67108864 bytes transferred in 4.043 secs (16,594,884 bytes/sec)

      # dd bs=128k count=512 if=/dev/zero of=/var/log/pf/64MB.bin
      512+0 records in
      512+0 records out
      67108864 bytes transferred in 3.980 secs (16,858,338 bytes/sec)


      Here I have written 64Mb to a San Disk Ultra II, first with 64kb chunks and then with 128kb. I did this because I usually use 64kb chunks and thought that 128kb would be faster for CF. Turned out to not be so, unless dd is writing 128kb chunks but the writes are being committed to the file system at no greater than the filesystems block size at a time.

      The two last dd's are the same thing but being written to a 120GB Seagate 7200 RPM PATA drive. Both the CF and HDD are directly connected to the on board IDE controllers of a Sun Ultra 10, each seperately as masters without slaves.

      The IDE controllers on Sun Ultra 5/10 motherboards are garbage BTW. They can get the best out of the CF cards I have, but certainly not the Seagate HDD, which does about 2-3 times better transfer rates in some of my PC's.

      I feel compelled now to do these tests again but to raw devices instead of to files within a filesystem. If the results were that 128kb block size filesystem is likely to be many times faster than a filesystem with much smaller blocks, I might be inclined to build filesystems with 128kb blocks on my CF based machines. But I think I would be limited to 1024 files on a 128Mb slice. Which might not be workable.
      --
      War crimes, torture, lies, illegal spying... Would someone give Bush a blowjob, already, so he can be impeached?
    2. Re:the number of writes is 10,000... by RzUpAnmsCwrds · · Score: 4, Interesting

      Your results are not indicative of flash performance - CF is simply not that fast. I frequently get 10MB/sec with my USB 2.0 SD card reader and generic PQI 1GB SD card.

      Flash can be *very* fast. Remember, you can interleave many flash chips using RAID-like techniques without the cost of having multiple disk assemblies.

  14. Flash disks that look like mag disks by nadador · · Score: 3, Informative

    They're out there in the embedded market, where your option is paying more for a flash disk or having your spinning mag plates fly apart because of shock/vibe.

    http://www.m-systems.com/Content/Markets/Embedded. asp

    As others may have noted, there are different kinds of flash, some that have good write performance, some that have good read performance, and some that have both.

    And if you want to pay, you can get an Ultra320 flash disk:

    http://www.m-systems.com/Content/Products/product. asp?pid=41

    --

    Outside of a dog, a book is a man's best friend. Inside a dog, its too dark to read.