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Seagate Releases Hybrid Hard Drive
An anonymous reader writes to tell us Seagate has released a new hybrid hard drive. This new drive adds the speed of a solid state drive to the conventional hard drive. Originally designed for laptops this new drive comes in 80, 120, and 160 GB flavors and features 256MB of flash memory.
Didn't samsung or some such outfit already do this?
http://www.pcworld.com/zoom?id=138102&page=1&type=table&zoomIdx=2 -attached to- http://www.pcworld.com/article/id,138102-c,harddrives/article.html
Both hybrids, Samsung AND Seagate were not only more expensive, they were considerably slower in tests vs. a traditional harddrive. I understand the drive to be green, but I think I'm going to wait a few years before jumping on this bandwagon!
Can't read the article but this will help understand about the Hybrid drives.
Since laptops can't support the faster speeds that their desktop brethren, any access time improvement is desirable. You can keep your most frequently used data on the Flash or as a buffer, such as during a movie. Another benefit is that flash takes less energy to read than a HDD.
Here's also a review of the drive itself
import system.cool.Sig;
I'm assuming (TFA is slashdotted) because the flash is used as kind of persistent cache. If so you could confidently defer a write onto the actual platter until you are doing other things in the neighborhood, confident that the data will be there if something goes wrong like a power failure or crash. I don't think it would do much for read caching, for which volatile RAM is fine.
Statistically, 256MB of pending sectors is probably enough to get most of the potential benefits from reorganizing writes to the platter. And if you sell a gazillion of these, a buck saved on each unit is a gazillion dollars of profit.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Windows has this thing to let the drive go to sleep when you're not using it... ...except it never does because Windows is always syncing it or doing something. It never gets enough idle time to actually spin down.
If these drives could fool Windows into letting them go to sleep we might be onto something.
No sig today...
For Hybrid Hard Drives to live up to promises. After a bit more digging - There is still a lack of results from this drive, although boot time and power savings are starting to show up. RAM caches have been around for years, and getting even 1 GB of flash memory is getting down to pretty reasonable levels. Why is this commanding a 30% premium and delivering unspectacular benefits? Unless there's a solid standard behind addressing for HHD's exists, there's no point in blaming BIOS or Vista for a problem that could also be addressed in on-drive logic.
Meh.
Actually, you have: http://msdn2.microsoft.com/en-us/library/ms940846.aspx (it's the first thing I do on a new installation of Windows)
Integration can solve a key point which is data integrity during an abrupt power event.
(see above).
AIK
It's ironic that hybrid cars save energy by spinning a platter and hybrid hard drives save energy by not spinning a platter. It's like blowing on your coffee to cool it and blowing on your hands on a brisk day to warm them. If we could just hook these devices up in round-robin, we'd have a perpetual energy machine!
This is about having longer laptop battery life. These days, processors are pretty good at throttling back. So the next big consumers are the harddrive and the screen (or rather its backlight). Well, hybrid harddrives offer a potential solution. Cache frequently needed data and small writes to flash, and you can spin up the drive platters less often. That saves power which increases the time you get on battery. Also it actually will make a laptop MORE responsive in that if the disk is spun down, the flash can handle things as it spins up so everything doesn't have to come to a halt waiting for it.
I don't know how much of a use these will be in desktops, but in laptops it seems like a really good idea. Also, Seagate drives normally perform slower than the competition. In basically all the tests I've seen, their drives are on the bottom. Of course we are talking a difference of a few percent at most, and perhaps that's also the reason their drives last longer. Maybe they don't push them so hard.
Around 1956, electronics makers began selling hybrid radios with both vacuum tubes and transistors. Emerson's vest-pocket portable model 843 used tubes in the rf stages and a pair of plug-in transistors for audio output. A 6 volt battery lit up the tubes and transistors, while a 67 volt battery kept the tubes' electrons jumping from cathodes to plates.
From Emerson's adverts: "Transistors are so tiny they must be seen to be believed. Transistors are so sturdy they won't break... They will last for life!" and give "greater power without distortion - full reproduction of voice and instruments, balanced tone quality, and greater power output with less distortion, not to mention low battery drain"
What other mixed hybrids have came along? Was there ever a hybrid horse and car?
I'm imagine they'd use this as a write-through cache. When you write data to the disk, it stores it in flash. Because a write-through cache can be quite effectively implemented in a ring-buffer (with reordering within a moving window for efficiency), you get perfect wear levelling without any complex controller logic. That means that it will work for writing 256MB times the number of rewrite cycles. Cheap flash has 10,000 rewrite cycles. My current laptop has been on for 30 days and has written 172.85GB to disk in this time. That gives 5.76GB/day of writing, or 23 complete write through the cache per day ignore, for now, that some of those were large linear writes, which would probably want to bypass the cache). For 10,000 rewrite cycles, with this usage pattern, it would take 435 day (1.2 years) to wear out the flash. This is, as I mentioned, assuming very cheap flash. Slightly more expensive stuff can get 100,000 rewrites, giving 12 years. If the mechanical parts of a laptop hard drive lasted 12 years, I would be very impressed. They should last longer with this kind of system, because it can batch writes a lot, and reduce the frequency of spinning the drive up and down. You also won't need to spin up the drive to read back data that you've only just written, which could help some poorly performing swapping algorithms (i.e. all of the ones used by 'modern' operating systems).
By the way, flash has a slight weird characteristic that you can write to it with a byte granularity, but only erase it with a block granularity, and it's the number of erases that cause the problems.
I am TheRaven on Soylent News
What is ReadyDrive:
http://www.microsoft.com/windows/products/windowsvista/features/details/performance.mspx
I'm summarizing what I learned from the German c't computer magazine, which has tested the various new technologies like ReadyDrive and others in Vista and also tested Flashdrives and Flash memory in general. Read the current issue of this magazine for in-depth analysis.
1) Pure Flash disks have only ONE advantage over harddisks: they are less sensitive to mechanical stress. In real-life scenarios, they don't safe power, and they are most definitely not faster than 2.5 inch drives. They ARE faster than 1.8 inch ones often used in ultra-mobile PCs, so there they indeed provide a benefit. For everyone else: especially write performance sucks compared to modern 2.5 inch disks, and read performance is at most en par. True, they don't need to position any heads so random access should save time - but according to the real-world tests made by c't that benefit isn't noticeable.
2) c't testers were very suspicious about how long Flash memory could survive as HD replacement where writing happens all the time, and yes, Flash cells have a limited lifetime, one cannot write too often. That's the theory. In practice c't testers were unable to make even the cheapest Flash USB stick show any sign of memory loss even after something like 16 million write cycles, when they gave up further testing because that's many many years of real-work usage. (pg. 104 of c't 21/2007)
3) Intel TurboMemory or MS Vista SuperFetch, ReadyBoost or ReadyDrive were shown to provide no measurable benefit AT ALL.
Suspicion of Hitachi and others seems to be that the current implementation in Vista isn't quite finished and SP1 should provide an update, and second the amount of Flash memory is waaaaaay too small.
Original article (German): http://www.heise.de/ct/07/21/100/
Why does any of this require OS hooks? If you're going to have OS hooks, you might as well glue a USB thumb drive to the hard drive and be done with it. (And in fact, an md-like linux driver to combine two block devices in a manner like the above would be a great hack.)
http://en.wikipedia.org/wiki/Wear_levelling
Nah, it's not worth it. Turning off last access time (BTW, it's turned off by default in Vista :) ) cuts my C++ project building time by 30%. I don't think any kind of intelligent defragmentation will be better.
No, flash memory can be quite a bit faster than that. Most of the time the limiting factor is something other than the flash. USB2 can only do 480megabits/s, and that is bursts, using something faster than that would be a waste. Even having something that can do 480 tends to be a waste as most of the time the transfer is much slower.
As for SATA drives they don't normally do 100MiB/s unless the information is already in cache on the driven. The flash memory is basically there to be a larger cache which is persistent across boots, allowing for the bootloader, kernel and a few essentials to be guaranteed a faster access time. Any additional items that go in there depend upon what the specific manufacturer specific algorithm does.
The size of the flash is like the size of cache on a harddisk, bigger isn't necessarily better. You could give a HD 30mb of cache, but if it is using a poorly designed caching algorithm, the difference can be nonexistent if the important stuff isn't in it.
In this case, 256 ought to be enough for present day computing. Even Linux is a fraction of that size, sure you could include a few utilities that regularly run during start up along with the kernel, but when you start to get beyond a quarter gig, you are beginning to get into things that run less predictably.
Here is an alternate article for the slashdotted original:
Having spent hours, days, years studying the effects of hard drive defragmentation, let me put the kibosh on 'intelligent defragmentation' here and now.
Defragmenting the files themselves gives about 20% of the potential benefits of defragmentation.
Defragmenting the file allocation table (FAT on FAT/FAT32 file systems, or MFT on NTFS file systems) gives the remaining 80% of the performance boost potentially given by defragging.
In the big scheme of things, it honestly doesn't matter whether the most recently used files are at the beginning of the drive, next to each other, or on opposite sides of the drive - if the file allocation table (or MFT) is sufficiently fragmented. Frag out the FAT/MFT bad enough over time, and simply defragging the MFT/FAT will make your computer run an order of magnitude faster.
Want the bad news? Windows doesn't ship with a FAT/MFT defragger (well through XP. Not sure about Vista.)
Only way I know to do it is with aftermarket software like Diskeeper (excellent product, BTW, 99% of the time.)
Glonoinha the MebiByte Slayer
It works on any Windows since Win2k.
You can also use fsutil utility to do the same thing: http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/fsutil_behavior.mspx?mfr=true
No, that's not correct. Samsung is shipping hybrid hard drives for over half a year now (see, for example, http://www.engadget.com/2007/03/07/samsungs-hybrid-hard-drive-hhd-released-to-oems/).
Recently, they even blamed Microsoft for the poor performance of hybrid hard disks on Windows Vista (in German, http://www.heise.de/newsticker/result.xhtml?url=/newsticker/meldung/97021&words=Samsung%20Hybrid&T=samsung%20hybrid)
The real world benefits of using flash as a cache layer between the harddrive and the computer, either through hybrid drives, don't seem to have materialized yet.
With my thinkpad there was an optional gig of flash that I ordered. After I downloaded the drivers and got it all set up, I found that there wasn't any noticiable difference in speed, or harddrive usage. However, I did notice that it interacted poorly with the "active protection" feature that stops the harddrive whenever the computer is in motion. Whenever the computer was unplugged, the flash cache was turned on, I could simply shake my computer (thus activating active protection) to get a blue screen.
Furthermore a little research showed that benchmarks on flash caches being sold right now offered no performance benefit whatsoever.
If there's no performance benefit, why are they trying to sell these things to people? I've seen some handwaving over the idea that flash *might* keep the harddrive from spinning most of the time and thus save battery life. However, when using the flash I saw no noticeable benefit.
Having an extra layer of cache in the system architecture seems like a good idea on paper, but in the real world the consumer is buying totally worthless pieces of hardware that do not improve performance one whit, and have never been proven to improve battery use.
From TFA:
I am a bit surprised to find, that there is a market for exploding laptops..
You might want to check out your new drive out-- It seems to have some data loss.