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It hasn't been for ages... Yup, decades I believe.

The performance bottleneck is the disk and it has been forever. You want a really fast system today? This is what you need:

http://www.m-systems.com/site/en-US/Products/IDESC SIFFD/IDESCSIFFD/Products_/SCSI_Products/FFD_Ultra 320_SCSI.htm

320Mb/sec burst rate, 40Mb/sec sustained and key... 0.02ms access time. It's the biggest performance upgrade you can make to a computer.

Why is this modded interesting? Solid state RAM drives aren't even close to being in the same market segment as SATA drives.

In the case that a "normal" filesystem is used, such as FAT, it isn't written out to the chips. NAND flash has special requirements about how it is written that prevent a normal FS from being used on it. There is a software layer between the filesystem the operating system sees and the flash chips. The operating system does not directly write to the flash chips unless it is using a flash filesystem. FAT32, ext2, and other non-embedded filesystems are not written directly to the flash.

Here is a company that sells flash chips that can be used with normal filesystems:

http://www.m-systems.com/site/en-US/Technologies/T echnology/TrueFFS_Technology.htm

On that diagram the DiskOnChip is the physical device. You can see that there is quite a bit going on between what the operating system "sees" and what actually gets written to the chips.

Flashdisks are much more reliable then any conventional harddrive. They claim >5,000,000 write/erase cycles and unlimited reads. Unites States defence department is using them for reliability issue alone.

M-Systems (top flash disk producer) states this:
(copied from the website)

Top Reliability & Endurance
** 99.999% reliability
** >1,400,000 hours of actual (in the field) MTBF
** Embedded EDC/ECC, based on BCH Algorithm
** Data integrity under power-cycling
** TrueFFS® technology: bad blocks mapping-out and dynamic wear-leveling algorithms
** >5,000,000 Write/Erase cycles; Read unlimited
5-year warranty


Source link:
http://www.m-systems.com/site/en-US/Products/IDESC SIFFD/IDESCSIFFD

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

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

>5,000,000 Write/Erase cycles, unlimited Read

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

I am literally drooling over that beast. However, I notice that it meets just about every "military grade hardware" spec a data storage device can, and there's no (easy) way to figure out the price. Anyone know what that might be?

I, for one, would LOVE flash drives to replace HDDs but would not feel comfortable doing so until a model up to these specs (read/write time and cycles, not the military encryption and ruggedness) is the norm. If the 128gig model of the m-systems drive is, say, $3k-$5k, then it would be much cheaper to put together a RAID 1,0 setup with 4 or more 128gig hard drives. I'm aware this obviously isn't a solution for LAPTOPS, but it'd have better reliability, better read/write performance, and have $2250-$4250 to buy my set of 5000 custom ceramic poker chips I'm saving for.

here you go:

>5,000,000 Write/Erase cycles, unlimited Read

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

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)

The m-systems read and write speeds vary a lot between drives depending on the interface. They are probably all slower than an average HDD. http://www.m-systems.com/content/Products/FFDFamil y.asp

Cenatek pci ram disks

BitMicro

M-Systems

You could probably find one for normal sdram, but to find a device that goes from 40/80pin ide to laptop SO-DIMMS is going to be a challenge.

The usual market for these things is low unit-volume embedded applications. They develop a protoype using garden-variety PC harware, then just swap out the hard drive for flash. The unit volume is too low to justify a hadware re-design.

You can "roll your own" flash storage, but then you have to do your own error correcting soft/hardware. Or you can get a module and dispense with cabling without having to re-work the system architecture, at the cost of spinning your own board layout. It's all a trade-off between development cost and price/performance.

It seems to me Microsoft could do the same thing for the Nvidia emulation rights they did for DVD playback. The only reason Xboxs don't play DVDs out of the box is because that requires a license fee to the DVD consortium per unit and they wanted the avoid that to keep console cost down.

Thus you had the Xbox "DVD playback kit", the cost of which included said licensing fee. I would think that if the money was right Microsoft could work out a deal with Nvidia that allows emulation(or perhaps even the inclusion of the original chipset) in a "kit" that plugs somewhere into the new unit.

That said, I believe some games(notably Halo and Ninja Gaiden) used a Gig of the hardrive as a memory cache. Micorsoft has a deal with M-Systems to build solid state hardrive-like storage. You might need a kit and one of these plug in drives for backwards compatibility, but I wouldn't be surprised to see something like this. I'd be buying one of these drives in the 40Gb range anyways for custom soundtracks, downloadable content, and holding my Xbox1 saves.

First of all, if you are this paranoid, you CAN buy EEPROM-based hard drives which can competely erase in five seconds. Try here, but hold on to your wallet first.

Second, if you did try a complete magnetic erase, you would completely destory the hard drive. There are certain magnetic "marks" on there which mark the locations of the tracks. They are written at the factory, and cannot be restored by the user.

MS has said it WILL NOT equip its next Xbox with a hard drive. They have hired on M-Systems an Israeli flash mem maker to replace the HD. Supposedly with something like this, but this flies in the face of most of the things this system is supposed to be capable of. Can they afford to give it a large enough solid state HD to work as a DVR/Tivo? Or to install and run PC games? I think not. So I guess we shall wait and see.

What characteristics do you want? There are two major types of solid state drives -- battery-backed ram, and flash ram. Both are expensive and small. Only one is fast.

My requirements were essentially (1) no moving parts, (2) affordable if not cheap, and (3) small. I settles on one of these. Debian is fine on 128MB, with 512MB of ram and no swap. Performance, it should be said, sucks. The next step up, for slightly more performance, much more capacity, and a whole lot more cost, is here; but I wanted to avoid using a case that needed drive bays, plus I haven't pockets that deep.

Neither of those is likely to be what you want for a database system, though. You're probably more in the market for a bunch of ram and a battery, unless your primary concern is reliability. If speed is the goal, you want this, or, for more capacity and more money, this. Note that I haven't used either extensively, and in playing around with the rocket a little, I was surprised just how much of a bottleneck PCI became. Also, the rocket doesn't have a battery... so really, unless you have a board with 8GB of memory, and you just need another 8GB of low latency space, it's not such a great deal today.

If you fit into any of the niches above, solid state is wonderful. It's always more expensive than you think, though. And for any database systems I've dealt with, a disk is without question the way to go, perhaps with more memory on board. But if you want any further tips, I'm glad to help.