Samsung Ships Hybrid Hard Drives

writertype writes "ExtremeTech reports that Samsung has become the first company to begin shipping hybrid hard drives as discussed last fall on Slashdot. (Some photos here.) Unfortunately, there's no word yet (beyond 'soon') on when retail shipments will begin, or when (or if) 3.5-inch models will be available. Note that these hybrid drives are different than the ReadyBoost USB flash drives optimized for Vista; hybrid drives contain a smaller amount of flash, and work as a write cache for your notebook drive, extending battery life."

Re:well

[bendodge]

A new kind of flash was developed last year that had much faster read/write (closer to RAM) and didn't deteriorate. I suspect that kind is what these will use. (Unfortunately I don't remember the name...)

Re:Linux

[morgan_greywolf]

If they use a standard interface like SATA, IDE, or even USB storage, then no special driver is required in the kernel.

Re:well

[yog]

It's more like 1,000,000 writes, but your point is taken. Perhaps the driver takes this into account--store many small and frequent temporary files such as browser cache files into RAM rather than flash, then dump them all to flash or disk rarely, but this implies a lot of intelligence on the part of the driver.

According to PC Mag link from the article, only Vista has the correct driver to use this drive.

It sounds like a nice innovation. Now to get from hybrid drives to biofuel laptops that run 8 hours on a thimble of ethanol ;)

Re:well

[SScorpio]

As someone else has already stated, yes flash is still limited but not as much as it used to be. These hard drives are aimed at laptops and I believe Vista requires them to be considered as "Designed for Vista" rather than Vista Ready.

The point of the flash is to provide a nonvolatile write cache which will then spin up the drive to write a queued data after the cache is filled. This is supposed to have a significant effect on the battery life of laptops.

Re:well

[NMerriam]

Isnt flash only good for ~30,000 writes?

The have limited cycles per sector, but the drives automagically allocate writes over the least-used sectors. In practice, a modern flash drive should have at least the same lifespan as a spinning disk if not longer.

Re:well

[Jaseoldboss]

PRAM [wikipedia.org] has the properties you describe. Although it isn't a type of Flash memory so I doubt it's the one present in hybrid drives.

Re:well

[Nasarius]

Linux must get full support for NTFS.

*tap tap* ntfs-3g [ntfs-3g.org] -- I'm using it now, and it's performing nicely even under pretty heavy BitTorrent load. ntfs.fsck still needs to be written, but the situation is now vastly better than it was less than a year ago.

Re:What I really want to know is...

[drinkypoo]

The idea is that the OS handles this and automatically caches frequently-used files. But it's also used as a delayed write cache to keep you from having to spin up your hard drive due to infrequent writes (like log entries.)

Re:What I really want to know is...

[Dan Ost]

The flash in the hybrid drives won't be used as that kind of cache (you're thinking of the Vista's ReadyBoost).

This flash will be a write cache for the hard drive so that the hard drive doesn't need to spin up as often (this will potentially enhance your battery life). As you make changes to your data, it will be written to the cache and then flushed to the drive (a) when the cache is full or (b) when the drive is spun up for some other reason (a read, for example). Presumably, if the drive is already spun up, the flash won't be used at all and data will go straight to the disk.

Old news

[Intron]

The press release [samsung.com] from Samsung is dated April 2005. You can read more technical details there without all the annoying popups on ExtremeTech. Looks like the drivers which give the power savings were written by Microsoft. Planned ship date was late 2006, so they didn't fall too far behind.

I smell BS

[cybrthng]

Superfetch will shut itself down if it fails. It couldn't possibly cause a FS crash/corruption like you complain.

OTOH these drives could fail since they're not superfetch and they're potentially caching writes.

Re:well

[tlhIngan]

Wikipedia says that NOR flash is good for "10,000 to 1,000,000 erase cycles" and NAND flash has "ten times the endurance". Lets hope they've used the good stuff.

NAND and NOR flash are completely different types of flash chips.

NOR flash is good for holding code - it's basically nonvolatile RAM. You can execute code straight out of NOR flash easily by hooking it up to a memory bus.

NAND flash is good for holding bulk data. It's interface is strictly I/O based (like a hard drive) - you cannot directly execute code from NAND flash without copying it to RAM first. Some NAND-based devices have fancy tricks (Like samsung's ONENAND and M-System's DiskOnChip) where they put in some SRAM so you can execute, but they basically have to copy it from the array into the SRAM. (NAND flash also has stuff like "bit flips" where read data does not exactly match written data - and reading data can change it, but this is compensated for by using ECC codes in the "spare area").

All NAND-flash handling code has to handle bad blocks as a typical chip can have up to 2% bad from the factory.

The reason we use NAND flash is because it's extremely dense. While flash gets increasingly expensive as you go larger (32-64MiB is the "sweet spot" in price/storage for NOR flash), NAND flash achieves really dense storage. For the price of a 32MiB NOR flash, you'd get 1GiB NAND flash chip easily. So for things like memory cards and stuff which use I/O interfaces, the flash is exclusively NAND. NOR is used for stuff like BIOS code which doesn't change very often anyhow, and often just enough of it to have code where we can pull out data from cheaper storage devices (NAND flash and hard disk, for example).

So yes, it'll be the "good stuff".

Re:hard drives are going away

[TheAwfulTruth]

I don't see HD's going anywhere for the forseeable future.

Well yes, IF flash ram can overcome it's shortcomings AND cost which is extreme.

you can get 750 gig of HD for $350, probably less now, how much would that cost in flash?

And unfortuantely flash is about as reliable as HDs right now for long term use. Even though it is not mechanical, it still wears out and is subject to out of box failures. (Memory manufacturing is about as poor as HD manufactuing is these days based on the number opf bad flash mosdules I've run into.)

And... it is so very very slow.

So yes, it woulf be GREAT to get rid of the bulky, loud, power hungry, slow access, mechanical HD of the last century, but... there is really nothing even close on the horizon right now :( Sadly, flash just isn't practical at all in it's current form for anythig OTHER than small devices that only need a small number of gig in a tiny form factor.

Re:Combine RAM with FLASH to store fs journal

[AaronW]

There are RAM drives available [newegg.com] that use DRAM, but due to the refresh circuitry and whatnot it takes a bit of power so the battery will only supply power to the RAM for a limited amount of time.
Also, if the flash were removable (i.e. SD card, compact flash) then it could be possible to move to another machine.

Re:Wait for Intel PRAM

[Anonymous Coward]

A current-generation flash drive can support ~7 years of constant writing.

Re:Linux

[profplump]

The SATA interface most certainly has commands to handle this new technology -- you can send arbitrary commands over SATA, just like you can over SCSI. It's a generic data interface not a block-layer device controller.

You'd just assign the controller another LUN and document the commands it accepts. You could then make the flash disk part of the address space of the primary disk or you could assign each their own LUN for use as two separate disks, with the third "control" LUN accepting commands to copy between the first two out-of-band. You could even setup a system where "dumb" controllers could use LUN 0 and treat the disk as a normal hard drive, with either automatic or no use of the flash portion, and expose the same physical disks separately on other LUNs for advanced use by "smart" controllers. Take a look at any tape library or even an iPod for a similar example.