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SSHDs Debut On the Desktop With Mixed Results
crookedvulture writes "Seagate's solid-state hybrid drives have finally made it to the desktop. The latest generation of SSHDs debuted with a 2.5" notebook model that was ultimately hampered by its slow 5,400-RPM spindle speed. The Desktop SSHD has the same 8GB flash payload and Adaptive Memory caching scheme. However, it's equipped with 2TB of much faster 7,200-RPM mechanical storage. The onboard flash produces boot and load times only a little bit slower than those of full-blown SSDs. It also delivers quicker response times than traditional hard drives. That said, the relatively small cache is overwhelmed by some benchmarks, and its mechanical sidekick isn't as fast as the best traditional hard drives. The price premium is a little high, too: an extra $30 for the 1TB model and $40 for the 2TB variant, which is nearly enough to buy a separate 32GB SSD. Seagate's software-independent caching system works with any operating system and hardware platform, so it definitely has some appeal. But dual-drive setups are probably the better solution for most desktop users."
"Don't meddle in the affairs of a patent dragon, for thou art tasty and good with ketchup." ~ohcrapitssteve
They seem to have forgotten a little defect. SSDs have a low failure rate, high speeds, okay prices, but everyone's scared of flash memory degradation after a number of writes. Some crappy one would get 1500 write cycles on a chip but OCZ ones get 9000 which, even at my high usage on a 128GB drive, is at least 8 years before it fries.
So Seagate decides to take the biggest pitfall and hated feature and put it into a hybrid drive. All data written to the gigantic drive is passed through that 8GB buffer first. Flash memory that can put up with that amount of writes over the long term doesn't exist. These drives would maybe last a year or two if you're lucky.
I've had one in my desktop for a couple years now.
Came out for the desktop and everything else for that matter in 1995. Get with it, people.
Linus Torvalds agrees with you...
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
I must say I find Linux's bcache much more appealing than hardware hybrids. I'm also not sure how this new hybrid drive would cope with software full disk encryption.
I had one of the laptop versions for about a year and a half now, and it's definitely an improvement over a traditional drive and considerably cheaper per GB than an SSD.
I'm not sure why the majority of the population wouldn't opt for these as they still give you decent capacity and speed over dedicated HD or SSD drives.
Sure they're not as good as a dedicated setup with a SSD and a HD, but then again, the average user can still install everything on their C: drive without making any changes from the default installation.
I looked at buying one of these. Writes don't really go to flash. Selected blocks are asynchronously copied to flash.
There's cool way to avoid the cash over use you mention that I wish someone would make in an under $500 drive. Have 4GB of flash, 4GB of DRAM, and a capacitor. Random writes go to DRAM, making random io a thousand times faster. On power failure, the capacitor flashes the contents of the DRAM to the flash. You get the speed of DRAM, crash safety, and 3TB of capacity from the underlying spindle.
I've been using a conventional hard drive paired with a SSD in Apple's Fusion drive configuration. This is only for Macs, but it makes it possible to use whatever size SSD you want, and the system automatically keeps the most recently written data on the SSD, saving the user the trouble of having to decide what to keep on the SSD and what to keep on the HD. In practice, the speedup is quite dramatic.
Well, in that case you could actually just skip the flash entirely.
The RAM could write directly to a dedicated area on the hard disk in the event of a power failure - sort of like how hibernate / suspend to disk works now.
Try reading again. 8 GB of Flash. It's not the same as a 65MB cache on a standard drive, it's more like two drives bundled into one package with the most used files 'cached' on the 8 GB of Flash. I'm not clear yet on if the files are actually cached (meaning there is another copy on the 2 TB HDD part), or if they live normally in the 8 GB Flash part.
with actual real world write speeds of around 20 MB/s, that capacitor would need to spin the drive for three minutes. That would be one hell of a capacitor. Flash chips use less power and are faster, so they could run long enough on capacitors that actually exist.
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For one thing, it is annoying to have to separate the OS and whatever apps you want to launch fast on to a tiny drive from everything else.
I just put / on the SSD and /home and /var (if it has to hold a lot of data) on the hard drive.
Oh, sorry, are you running one of those weird old operating systems that have that drive letter nonsense?
I really do hate overloading acronyms. SSH / SSHD is pretty well known already. It's what most unix folks (and I really do hope that that is the majority of slashdot readership) use to log on to servers every single day.
C'mon.
"Rune Kristian Viken" - http://www.nwo.no - arca
No no, don't worry about the intel one. For Linux there's bcache and flashcache. Like with any multi-drive RAID-ish system, better to go with a plain software solution than a software solution hidden in a proprietary driver. There is also ZFS with support for read cache devices, but you won't get great boot speed because it's not persistent across reboots (there is a patch in one version of ZFS). Basically a bigger RAM cache that also doesn't get wiped out by applications
one of the 2.5" drives. Benchmarks are a dubious thing - sure you can overwhelm the cache but in real world use that is not going to be an issue. Most users are doing the same thing(s) over and over and the drive optimizes to keep the necessary files in the ssd for rapid access. Likewise, modern drives, even the 5400 variants, are fast enough to keep up with video recording. So this really boils down to - are you willing to take a performance hit on the odd times you actually read or write a gigantic file in exchange for near equal everyday performance and a huge capacity at a very cheap price.
In my caae, the answer is a firm yes.