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The Benefits of Hybrid Drives
feminazi writes "Flash memory is being integrated with the hard disk by Seagate and Samsung and onto the motherboard by Intel. Potential benefits: faster read/write performance; fewer crashes; improved battery life; faster boot time; lower heat generation; decreased energy-consumption. Vista's ReadyDrive will use the hybrid system first for laptops and probably for desktops down the road. The heat and power issues may also make it attractive in server environments."
Windows creates an immense swapfile anyway - why not just get the system to do it on either a designated part of the hard drive, or on a USB 2.0 flash drive?
Actually, has anyone tried that? I expect you could see a decent increase in performance that way.
Windows' swapfile usage is pretty similar to the way Linux does swap, except that Windows uses a file instead of a partition. By default it's 1.5 times the amount of RAM installed in the system and is made all at once to ensure a contiguous file. On systems with plenty of RAM it's still good to have because it means the OS can commit to having plenty of memory for applications which request a lot, most of which they might never use. Without a page file 10-20% of physical memory is wasted because the OS has committed to having it (think Photoshop, etc).
I don't know how well the pagefile would work on a USB drive since if you're using much swap you're already seeing serious degradation. Besides, flash drives still suck at write speeds, being many times worse than even an old IDE drive. That's the biggest problem with integrating the two technologies I would think--making sure that you don't introduce bottlenecks due to stuff like that.
"What do you despise? By this are you truly known." --Princess Irulan, Manual of Muad'Dib
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An age old method called write leveling. In practice it usualy doesn't work since most people do it with USB thumb drives and/or flash memorycards which are all removed on a regular basis so the reader/writer of the media gets changed allot or the controler doesn't impliment write leveling. As such the write leveling never really gets done very well. With a system like this the write leveling would be exact and the flash memory would end up outlasting the moveing parts of the hard-disk. Also as parts of the card went bad the controler would skip over those sectors in the future which would lead to it working even longer. Even one part of a regular hard disk goes bad and your boned completely.
It was in the original engineering design, but the lawyers said it would be cheaper to just include a warning in the fine print of the warranty.
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The technical specifications of the flash memory in my USB drive says that it is guaranteed to work for, at most, 100000 (i.e., one followed by 5 zeros) writes. People do not talk about this limitation, but I have seen this limitation written into the technical specifications of the flash memory in many devices
But, on the other hand, how often do you write to your windows folder? There's the monthly update, the occassional reg hack, but all in all, once it's established, that's a pretty static area of your drive. I could see this as an incredible benefit to system files, which, as has been discussed oft here before, the big reason for this.
Loading your PPT file in flash won't help bootup. Loading that fuster-cluck of the system32 folder, though, would.
Someone will be awfully upset when she makes a final save of her million-dollar PowerPoint presentation for the CEO and discovers that the save is the 100001st write to the hybrid drive.
Backups? Alternate locations? If this is what it takes for them to learn the necessity of redundant copies, it's even better.
There should be some level of safeguard built in that anything user created should be stored to the magnetic part of the drive, my documents, program files, but they should have this anyway. I mean, nothing like the last save and then having to call Dell because your drive is spitting out an Error Code 7...
Depends on what you're doing. For example, if you run IIS, your log files (by default; you can change this) are in %WINDIR%\Sytem32\LogFiles. That's going to have a lot of writes. Any new hardware or software installation may cause writes to %WINDIR%. There's a lot of other stuff that legitimately writes to %WINDIR% like installing a new printer (think roaming -- you may print to a different printer every day), the .NET Global Assembly Cache, Visual Styles and themes, and a whole lot more. Whether these things should be in %WINDIR% or not is a different question. The point is that using flash for %WINDIR% under the assumption that you'll not write there very often is a little naive. Perhaps Vista reorganizes %WINDIR% somewhat so that fewer processes need to write there.
All of this is a moot point anyway, because this use of flash is only as cache. Anything written to the flash drive should eventually be flushed to the hard drive. Similarly, if you've exhausted your write cycles and try to write to the cache, it should seamlessly catch the fault and go directly to hard drive. In that case it would be nice to give an occasional notice that your flash chip is exhausted and you need to replace it, but you should not risk losing any data. I'm not a big fan of on-board flash simply because it may be unreplaceable. Any onboard flash chips should not be surface-mounted, but socketed like RAM, CPU, or the clock battery. That will require some standardization on sockets, but as long as there are only two or three different options and the designers of said options let others build chips using that interface (*cough*Sony*cough*) it shouldn't be a problem.
In the long run, I think computer manufacturers will love this. How likely do you think your parents will be to replace their onboard flash when they run out of write cycles? The average consumer will just buy another PC for a couple hundred dollars rather than buying a new flash chip and installing it (or paying someone to install it).
How soon do you think the conspiracy theories will start up that manufacturers like Dell are intentionally shortening the life of onboard flash through factory "testing"?