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Notebooks w/ RAID? 62

Posted by Cliff from the fault-tolerance-for-devices-that-really-need-it dept.
macemoneta asks: "Are there any notebooks available on the market that support (bootable) RAID (at least two 40GB+ drives as RAID0 and or RAID1)? While the rest of the components in 'desktop replacement' notebooks are quickly getting up to snuff, the hard drives are anemic in performance, capacity and reliability compared to desktops. Being able to use software RAID to create high performance meta devices and high reliability meta devices would really kick notebooks into high gear. Before anyone complains about size, weight, power and heat remember that notebooks have gone from 12 inch screens to 16 inch screens and 486 to P4M in the last few years. Most desktop replacement laptops use the batteries as a UPS, since they usually only last 90 minutes or less anyway."
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Notebooks w/ RAID? More

Notebooks w/ RAID?

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  • Admittedly I am not a fan of big laptops. If you need to take data around, get a usb/firewaire HD. If you need a portable work environment, you can get an 800Mhz 256MB 30GB laptop in a sub 3 ound .75" thick form. For presentations a 3 pound laptop and a 3 pound projector so the job better than a 16" laptop screen anyway.

  • Multiple drives? (Score:3, Insightful)

    by Linux_ho ( 205887 ) on Thursday July 25, 2002 @11:17AM (#3951345) Homepage
    You would do well to simplify the question by asking if there are notebooks available with multiple hard drives. Lilo can boot to a software raid, so any notebook with two drives can do this. Whether the sound card or built-in ethernet/modem works is a different story, but you didn't mention whether those were important to you.
    • I wanted to eliminate non-bootable RAID configurations: drives off a PCMCIA controller or Firewire drives, unless supported in the BIOS. I'm not sure that all the notebooks that support multiple drives can actually boot from any/all of them.
      • I know, a guy wants what a guy wants, but what is it you are actually trying to accomplish?

        Faster throughput?
        Data protection against failure?
        Larger partition (one massive partition across two drives)?
        Impress your friends? (don't laugh, some social circles judge you on your toys)

        If your intent is to get more performance, I question whether software based RAID 0 is going to actually make your system faster, particularly if the CPU is already burdened with things like running the OS, doing compression, playback of whatever you are playing back ... I am not particularly confident that any software RAID is going to go noticably faster than direct access to a single (fast) drive.
        If you want to go faster consider SuperSpeed's disk caching products http://www.superspeed.com/ - in particular you can shadow an entire partition with a read write cache if you have enough RAM. If the dataset is too large for that they have a read write cache that is configurable also (but doesn't shadow cache the entire drive).

        Want larger partitions, impress your friends, or RAID 1 for data protection against hardware failure (this is going to SUCK for throughput though, if software RAID1) then most of the large Dell laptops can put a second drive in the removable bay for a second drive for RAID.

        Glonoinha
        • I use software RAID on Linux; the reason I'm looking for it on a notebook. Performance is excellent and CPU load is negligible (even on an old PPro200) even during intensive I/O bound operations. You can mix RAID0 for performance/capacity and RAID1 for reliability on the same pair of drives (different partitions), providing exceptional flexibility.

          You really should try it.

  • DELL Inspiron 8200 (Score:1, Informative)

    by Anonymous Coward
    DELL's new inspiron with the 64MB Geforce4Go will take two 40 gig drives and can software RAID across them with linux.
    beware of the expense -- its around $7K fully loaded with all options including multiple batteries which you will need if you use both hard drives RAIDed.

  • laptop drive limits (Score:4, Informative)

    by OpenMind(tm) ( 129095 ) on Thursday July 25, 2002 @11:34AM (#3951487)
    I'm not sure this is a good idea. Laptop drives, even the recent IBM enhanced models, are rated for a much lighter activity cycle than desktop drives. That is, push them as hard and as long as full-size drives , they are likely to fail on you. IBM is trying to fix this to make their 2.5 in drives suitable to blade servers. Still, RAID historically pushes drives hard enough to decrease the time between failures quite a bit. Combine this with drives designed for low load, and you're asking for trouble. I think the recommendation of a firewire external drive was a good one.

    • Re:laptop drive limits (Score:2, Informative)

      by thejson ( 315064 )
      I don't believe there's any reason to assume that using RAID would push the individual drives any harder than a single disk would be. I think this could be a good thing, especially for mobile desktop users. With RAID in a laptop, there would most likely be at most two disks due to space concerns. This would limit you to RAID 0 or 1. Consider RAID 0/striping: any reading or writing to the drive is split accross both drives, so in theory they should be doing half the work. However if one disk does fail, you're screwed, which is why this isn't a good option for a laptop (technically not even really RAID) Now consider RAID 1/mirroring. Each drive does the same amount of work as one individual drive would. There may be some additional overhead, but the added reliability is well worth it. If one drive fails, which is more likely to happen in a notebook, the problematic hard drive can be replaced without data loss.
      • I'm not entirely sure of the full rationale, only that I've come across quite a few references to increased disk loading in raid systems, in addition to plain old working experience. I think the particular stripesize/cylinder size ratio, stripe layout, etc. have a lot to do with how much effect this has. A striped drive tends to end up doing a lot more short reads as compared to long sequential reads. Depending on how well the drive heads are managed (easier to do well in hardware, IMHO) the increased seek activity can generate a lot of wear and tear. This is not as big a deal when using the RAID with large files and a small set of data consumers. Again, this is my non-hardware expert interpretation, but there is a lot of reference in the literature to the shortened life of RAID drives.
        • I've come across quite a few references to increased disk loading in raid systems

          Out of interest, could you point them out?

          I would have thought that disks in RAID systems are usually under increased load because RAID is often chosen for high load scenarios.

          Kinda like saying red cars are involved in 20% more accidents than other coloured cars, therefore you have a 20% increased chance of having an accident if you drive a red car. Without considering that there are actually 20% more red cars on the road than any other colour.

          PS, I just pulled the 20% figure out of the air to illustrate my point, I don't know what the real number is, just that there are more red cars on the road which can lead to ridiculously misinterpreted statistics and thoughts of voodoo and such.

          • I've looked a little closer into the references I could find on the web about decreased MTBF on drives in a RAID scenario. It appears that the way most people are viewing this is as as statistical phenomenon. If you have 6 drives with a fixed probability of failure, the whole set has a higher probability than the individual drives. I could not find any references, in the last 15 minutes, to increased loading, so perhaps that part was a phantom of memory. Either way, with low reliability drives, dividing the MTBF by two is not the best idea.
            • Yeah, but with a system thats back home infrequently might it be better to have a lower MTBF and the ability to repair the damage than a system that rarely breaks but when it does its catastrophic.

              • might it be better to have a lower MTBF and the ability to repair the damage than a system that rarely breaks but when it does its catastrophic.

                Exactly.

                If you don't need super performance, can't tolerate loss and can afford it, just mirror across some good drives.

                SCSI drives seem to have higher MTBF's and longer warrantees, so after a bit of research amongst them you should be able to find some reliable drives.

                If you need performance and cannot tolerate loss, RAID5 or RAID0+1 could be good for you.

                But regardless of your disk system choices, choose a backup method that has a reliable restore feature. ; )

        • Interesting. Either way, I wouldn't advocate striping on a laptop for reliability reasons anyway. I think mirroring has some notable advantages in a notebook, though.
      • Using software RAID (in Linux, for example), you can do both RAID0 and RAID1 on the same pair of drives, for different (matching sets of) partitions.

        You could setup a "work" partition set to be RAID0 for fast processing of large files (video data conversion, for example), while the rest of the partitions are RAID1 for protection from a failure.

        With software RAID, it's not an either/or situation.
    • But IBM is even having problems with their normal IDE drives...they need to fix those first! Also, why do you think IBM is getting out of hard drives. They just aren't good at it anymore... Remeber the 20 hour a day (i think it was) hard drives?
  • I would rather have a 15000 RPM harddrive, than 2 4800 rpm drives in a laptop. Space, battery, etc..

    • SCSI (Score:2, Interesting)

      by Rheingold ( 2741 )

      For a modern multi-tasking operating system like Linux or BSD, SCSI is a better answer than RAID. I've always found interactive use much better than with IDE, even than the newer ATA-100 and ATA-133 drives. IBM used to make RS/6000s with 2.5" SCSI drives and titanium cases. There were really sweet!

    • Ready for liftoff? (Score:1, Insightful)

      by Anonymous Coward
      With a 15k rpm drive your notebook will sound like a jet engine, and probably consume about as much fuel...
    • No, you wouldn't. Go find a 15000 RPM drive. Plug in just the power cable, and give it some juice. Once it's spun up, unplug it, and then start moving it around. I'll tell you, it's very interesting to have a hard drive fighting you. The same effect would happen when you started moving your laptop. And of course, giving that thing a hit when it's spinning would ruin your day.

  • Why? (Score:1)

    by imta11 ( 129979 )
    A two disk raid would only provide redundancy or increased speed for writing. There are no data collection boards I can think of that would produce data at a high enough rate to make ATA100 drives inadequate. I assume this is for some kind of embedded data collect device, in which case you may want to consider an array of wireless transport technologies to an offsite RAID. If is a redundancy concern due to mechanical trouble, look into solid state drives, which are gettig quite large.
  • At my place of employ, we've been pleasantly surprised with the performance of the latest latest laptop hard drives, actually. Compares quite favorably to anything but 7200 RPM drives, at least for what we do (software development).

    Depending on how you configure it, some Thinkpads can take two IDE drives. But I suspect your best bet is to get a pair of 3.5" drives in an external case and either hook up via FireWire or SCSI. I doubt that 2.5" IDE drives will take well to RAID 0.
    • Now THATS portable... It will go good with my car battery and inverter that I carry around in my backpack...I can make that thing run for days!
  • How about the Dell Precision M50 [dell.com]? Two HDD bays, the RAID would have to be software... expensive, yes - but it's an option.

  • Look at the Eurocom 8880 (Score:4, Informative)

    by compwizrd ( 166184 ) on Thursday July 25, 2002 @12:10PM (#3951766)
    The Eurocom 8880 has the capability for FOUR hard drives at once

    http://www.eurocom.ca/products/showroom/specs888 .c fm

    Has the capability for two cdroms/dvd-roms/etc at once.

    15.7" screen as well.

    No mention of weight, I suspect you don't wanna know.

    Eurocom has always been a little bit ahead of everyone else on getting things out :)

    I believe the TV tuner option replaces one of the media bays though
  • Perhaps this [smartdisk.com] would do the trick? It even comes with a Li-Ion battery.
  • SmartDisk (which I think either bought out VST or something) has a product called the FireWire RAID tower [smartdisk.com] for Macs that allow you to setup four VST FireWire hard drives and a battery, and using FireRAID software to create a RAID array. Since the max FireWire transfer rate is 400Mbit/sec (or 50MByte/sec), performance wouldn't be too bad. Another solution is a larger IDE to FireWire RAID enclosure, like one from MacAlly [macally.com] that supports Windows and Mac OS.

    Maybe in the near future, we will see Serial ATA RAID controllers utilizing a PC Card slot that supports say two drives in either RAID 0 or RAID 1, that would connect to drives and powered by either a battery or an external power source.

    Software RAID under Windows may not be the most optimal solution due to it's processor overhead, but it's still a somewhat viable option.

  • It would have to be software raid, but you can run two hard drives with newer dell laptops. Dell has a $30 carrier that allows you to use a hard drive in the media bay. For my inspiron 8200 the part number is 29MFN for a 9.5mm drive. For a drive, look at the IBM 40GNX with 8mb of cache. There are lots of discussions on this at dell's forums at delltalk.us.dell.com [dell.com] in the inspiron hard drive forum.

  • Not the unix way (Score:4, Interesting)

    by bluGill ( 862 ) on Thursday July 25, 2002 @12:23PM (#3951874)

    Sorry, but I gotta complain about your definition of desktop replacement. I want a desktop replacement laptop because I can take it to class and meetings. I love taking notes on my laptop for 8 hours without plugging in. Meeting minutes should be sent out within 1 minute of the meeting ending. When someone is in a meeting they should be able to get at the unexpected data they need that is on their desk, without leaving the room (that is the data is on the computer, so any computer can access it), not run back to their desk to price off a hard copy. Sure the batteries are a UPS, but if that is all you use your laptop for, a desktop with a UPS is cheaper and has a better keyboard, and monitor.

    When I need more power than is on my laptop, then I ssh over to one of our CPU servers (at my last job we had a couple machines set up for this), and display my apps back to the laptop.

    Laptop users should not have a big harddrive. They should have enough room for the OS, a few apps that they run on the road, and a copy of the documents they use often. Note I said copy, the master copy of these documents should be someplace that is always backed up, the laptop just has a copy for quick work until it can be synced with the master (two way sync). Other than that, long battery life, weight (the mass of even a heavey laptop is not enough to make a difference in gravity humans can stand, so weight is the critical), screen, keyboard, and interfaces are key.

    Remember laptops are stolen; droped and broke; and forgotten far too often to have the master copy of anything. They should be easially replaceable. Too expensive to be disposable, but too fragile to depend on any one.

    When you lock yourself into the desk is where I work, you miss the power that a laptop gives you. Get a laptop that you can use anywhere, wireless networking in the office (warning, security issues need to be addressed here), with a battery that is worth something. Suddenly the laptop goes from an expensive toy that to impress people to a useful tool that does things you couldn't get done otherwise.

    • Re:Not the unix way (Score:2, Interesting)

      by nomel ( 244635 )
      Do you realy get 8 hours? What Kind of laptop you have? Cause that's real nice...

      • Yep, a IBM thinkpad 390. It got just over 4 hours from a battery, and I had two. I only used the cdrom drive once in the year I had it, so removing the CD/floppy for a second battery was a good trade off to me. I was also careful to avoid using anything that took power, all the computing was done on the backroom cpu servers, and this was just a display.

    • That is the standard definition of 'desktop replacement', though. The one you refer to seems to belong to the subnotebook category.

      Even a subnotebook would struggle to stay up for 8 hours on standard batteries though - and the larger battery packs tend to cost quite a bit more.

      On the other hand, the original poster was slightly mixing up his terms too. It's really a desktop replacement *portable*, not *laptop*. Even my friend's slim 12.1" Vaio gets really rather warm - would not want it in my laps for too long!

      Michel

  • Cheaper option (Score:3, Informative)

    by bill_mcgonigle ( 4333 ) on Thursday July 25, 2002 @12:54PM (#3952090) Homepage Journal
    Wow, so many links to expensive hardware. Pick up a used Pismo powerbook (last black one). You can take out the CD drive, and replace it with another laptop drive. Sleds are available from VST, probably find some used ones too. OSX has software RAID-1 built in.

    You could use any of the black line, but the Pismos often had 500MHz G3's.

  • Huh? (Score:4, Interesting)

    by bellings ( 137948 ) on Thursday July 25, 2002 @02:48PM (#3952807)
    Being able to use software RAID to create high performance meta devices and high reliability meta devices would really kick notebooks into high gear.

    Can someone explain to me what a "meta device" is? And, can some explain to me what happens when you get a plurality of "meta devices?" I mean, what the hell is this guy blathering about?

    I'm sure other people are going to point out that RAID probably isn't the solution to the problem you think you're having. It's like hoping that forged connecting rods and pistons are going to make your Dodge Neon into a sports car. By itself, it's not going to do what you seem to hope it will do.

    Anyhow, if you want a good, decent, fast notebook get yourself and Apple.

    • Re:Huh? (Score:1)

      by Polo ( 30659 )
      He means a logical disk composed of two or more physical disks.

      The only reason I think anyone would want raid on a laptop would be for raid-1, where the two disks are redundant copies of each other. Even that would be a stretch.

      I think if they want speed in a notebook, they should just put in one faster drive instead of striping.
      • No matter how fast a single drive is, striped drives are faster...
        • No matter how fast a single drive is, striped drives are faster...

          It depends. If you have a perfect setup, transfer speeds are, of course, better. However, statistically seek times are going to be worse, because for any seek both drives need to seek, and they'll never get to the data at exactly the same time.

          But there is no guarantee that any random laptop with two or more hard drives is going to be a "perfect" setup. Who's to say that the controller and the drivers are going to be able to send commands to both drives simultaneously, and recieve data from both drives simultaneously? Given the strange and non-standard stuff wandering around on a lot of laptops, I wouldn't be suprised at all if software "RAID" striping ended up being crazy slow.

          I also want to point out that although striping has recently been given the cute nickname "RAID 0", it really isn't RAID at all. I shouldn't be too suprised if the fellow who originally posted this meant striping, because he seems totally unclear of the meaning of even normal english terms like "meta." He doesn't seem any more confused than most of the clueless wanks who get selected byt the editors for "Ask Slashdot" columns, though...

          • If you check the author of the question, the clueless one would be me. :-)

            I used the term meta device, because that's how Linux uses the term for it's software RAID, which is what I'm interested in using. Physical devices are combined into meta devices (/dev/md0, /dev/md1, etc.).

            In RAID0 both drives are seeking, but for different data. There's no requirement that the drives be synchronized in any way. Once the first buffer arrives to satisfy the request, the the application is dispatchable. Synchronized spindles were a technology that was used at one point, but the last I heard about it was about 15 years ago. FTR (full track read) in the drive firmware and similar competing optimizations eliminated the need for synchronization and the associated RPS (rotational position sensing), and RPS-miss condition you're describing.

            In RAID1, either device can satisfy a read, so read processing is slightly faster. Both devices have to acknowledge a write, which does reduce performance slightly, for the increased reliability.
    • Damn that mechanic...I better take back my pistons...

  • Side point (Score:3, Informative)

    by macdaddy ( 38372 ) on Thursday July 25, 2002 @03:09PM (#3952952) Homepage Journal
    I bought an Asus A7V333 with the onboard RAID. Once per minute regular as clock work the load spikes to 30% on top of what's already running. Once a minutes, regular as clockwork. Up and down real quick. Games stall, MPEGs stall, etc... The problem is apparently the RAID. I have 4 120GB WD 8MB cache models. 2 as regular drives. 2 as a stripe on the OEM Promise FastTrack133 builtin controller. If I disable RAID with the jumper, no spike. If I re-enable, regular spike. If I leave enabled and disconnect the 2 striped drives, no spike. It's got to be the RAID. Asus won't return my calls. I guess this means I'll never buy an Asus again and probably never buy a board with onboard RAID again. A buddy of mine blames it on the Via chipsets. Could be.

    That said, I'm not so sure you want to buy anything with onboard RAID. Perhaps you should look at a speedy Firewire drive.

  • Easily done (Score:1, Informative)

    by Anonymous Coward
    Get any laptop that can take 2 HD (Thinkpad would be my preference, install Win2k and setup active directory on both drives. You can then enable Win2k's software RAID, done. Setting up an array with 2.5" drives as been done before. Check out these articles at Tom's hardware
    http://www6.tomshardware.com/storage/02q 1/020301/i ndex.html
    http://www6.tomshardware.com/howto/01q3 /010906/ind ex.html

    About "macdaddy" clockwork spike. I would suspect the Promise driver is the problem. Try disabling the RAID controller and run the Win2k software RAID instead.
  • The capacity is limited to the data density that can be put onto the platters. You have to realise that there are not as many platters, and they are much smaller. In order to get even the same storage size from a laptop hard drive, the data density would have to be much much greater than that of a normal hard drive. This means that unless they stop making desktop hard drives that have the highest density possible at the time, laptop hard drives cannot, and will never hold as much data as their bigger brothers.

    Also, on reliability, you have to realise how much torture these little drives go through. They are banged around in your laptop case/backpack and moved while spinning. To keep it reliable, the manufacturer of my laptop drive says to only use the laptop on a stable flat surface (unmoving, not legs or anything like that) and to NEVER move the laptop when it is on. Your desktop drive never gets moved while on (well, the normal person never moves it), and is very rarely, if all, banged around (occasional lan party). In order to keep the angular momentum from being too great when they are moved, so they don't really wear out bearing and whatnot fast and to save battery power, they are made to spin much slower. A 10000 RPM hard drive wouldn't last nearly as long as a slower one, unless you never picked up your computer while it was on, or banged it around (just don't move it and it will most likely last as long as desktop drive, maybe even longer).

    Also, fluid bearings are getting very popular with
    the newer drives. This helps to keep them from damaging themselves when they are banged around when off.

    Why they don't use raid, I realy don't know. Most laptops support multiple hard drives (Toshiba), but most of the time they are removable. If you add another hard drive, where will you put it? If you have ever opened one of the newer (or even fairly old) laptops up, you will realise how crammed everything is. They are fitting a whole computer in the size of a keyboard. Adding another permanent hard drive, at least on mine, would require it to be quite a bit bigger (in terms of laptop size) because they would have to add room the size of the hard drive, plus some space for brackets. That would be about 2/5 an inch thicker. They could stack them without having to add much more room, but then you will have overheating, and once again, reliability problems.

    And, IMHO, these are what they claim to be, desktop replacements, not server replacements. Why would you really need a SCSI or RAID configuration? The time you will save loading, compared to a standard desktop hard drive might only add up to tens of hours a year. To me, thats not worth the *reliability* or price, except for the coolness factor...heheh

    They are just adding good cooling techniques (watercooled) that would allow for more compact cramming of parts. So now they don't have an excuse... :)

    If you want something that will last, buy a toughbook! These things are garanteed to not break if dropped onto cement from arms length. But they are big and heavy and ugly as hell.

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