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WD Explains Its Windows-Only Software-Based SSHD Tech
crookedvulture writes "Seagate and Toshiba both offer hybrid hard drives that manage their built-in flash caches entirely in firmware. WD has taken a different approach with its Black SSHD, which instead uses driver software to govern its NAND cache. The driver works with the operating system to determine what to store in the flash. Unfortunately, it's Windows-only. You can choose between two drivers, though. WD has developed one of its own, and Intel will offer a separate driver attached to its upcoming Haswell platform. While WD remains tight-lipped on the speed of the Black's mechanical portion, it's confirmed that the flash is provided by a customized SanDisk iSSD embedded on the drive. The iSSD and mechanical drive connect to each other and to the host system through a Serial ATA bridge chip, making the SSHD look more like a highly integrated dual-drive solution than a single, standalone device. With Intel supporting this approach, the next generation of hybrid drives appears destined to be software-based."
Yeah, that was a nightmare!
Linux already supports SSD-HDD caching with normal drives so if anything, it will probably already work or work with little changes. Otherwise, just pick up a tiny SSD and ignore this solution. http://bcache.evilpiepirate.org/
Nice troll, btw.
It isn't clear, exactly, from TFA what the drive will look like when you plug it in. Both components(the HDD and the SSD) apparently can function as SATA peripherals; but they are both behind some sort of bridge chip, type unspecified.
If the 'bridge chip' is just a reasonably generic SATA port multiplier, then an unsupported OS, or Windows without the driver, will just see two drives, the larger mechanical one and the smaller flash one. This would leave the way open for any OS with SATA and AHCI support to do whatever it prefers to get the best performance(on Linux, I assume that'd be at the filesystem level, with something like btrfs)
If the 'bridge chip' is some sort of proprietary oddity, and the vendor driver is required to even communicate with the flash portion(presumably at least some part of the drive will be visible as a normal SATA device, or booting without specific BIOS support would be a problem...), then that's pretty much worthless.
The iSSD and mechanical drive connect to
I believe I speak for the majority here when I say.... D'ARGH! KILL IT WITH FIRE NOW! This is yet another pathetic attempt by WD to marry it's crappy line of mechanical drives to SSDs in order to stretch their relevance out a little bit longer and keep them from having to retool their assembly lines and such to produce SSDs exclusively. Weeeell, good for you guys. But as my father would say: "Shit or get off the pot." Either switch to SSDs, and eat the cost, or stick with mechanical drives because they're cheap. But don't waffle and try to do both; You're getting the worst of both worlds then.
#fuckbeta #iamslashdot #dicemustdie
As an end-user, I'm NOT going to put up with a solution like this.
Even if it somehow performs better than current hybrid drives.
Even though most of my work is done on a Windows platform.
Hybrid drives are already a big compromise for minute gains.
Tying it to an OS choice?
NO FUCKING THANKS WESTERN DIGITAL!
In a budget situation I'd rather just put up with a competitor's hybrid or a plain old mechanical disk.
In a performance situation I'd rather just spring the extra cash for a real SSD. Better returns and more flexible.
Chas - The one, the only.
THANK GOD!!!
WD has taken a different approach with its Black SSHD
They'll have a lot more explaining to do, once some hacker, cracks the SSH password, starts pwning WD disk drives, and they begin to spew forth spam... :)
Uh, okay, whatever.
Guess I won't be buying one. Best of luck to those that do.
Note to ACs: I usually delete AC replies without reading them. If you want to talk to me, log in.
The dm-cache device mapper target was added to the kernel in Linux 3.9. bcache is apparently on track for 3.10
I see that you don't really understand what Apple's Fusion Drive really is. In Intel's SRT the SSD drive acts like a cache for the HDD. I hope I don't need to explain what a disk cache is and how it works. In the Fusion Drive on the other hand both drives appear as a single logical volume with the space of both drives combined and the OS decides which files get stored on the SSD and which on the HDD. From the Ars Technica article I quoted:
In a caching solution, like Intel's, files live on the hard disk drive and are temporarily mirrored to the SSD cache as needed. In an enterprise auto-tiering situation, and with Fusion Drive, the data is actually moved from one tier to another, rather than only being temporarily cached there.
Those are two very different approaches.
Think secure boot. If the 'bridge chip' has a key, that only the trusted driver can supply, then with UEFI and "secure boot", they have just locked down the machine to windows only.
You are being MICROattacked, from various angles, in a SOFT manner.
The nice thing about Seagate HHDDs or SSHDs or whatever the companies what to call them now is that they just work. You drop it in a system, it works like a normal drive but faster. The flash works like cache on a RAID controller or the like. It just speeds things up.
With this, there's mucking about. Even if you could use it as separate drives, why would you want to? If I want to to just some small SSD storage and larger magnetic, I can. In fact I do. In my laptop I have a SSD for OS and apps and an HDD (actually one of Seagate's hybrids) for media and samples. My desktop is the same but more and larger drives.
It just seems silly to me. An all hardware approach seems much better and clearly doesn't cost that much as Seagate's drives are not expensive.
It's not "lazy shits," it's "bean counters" that say software is cheaper than hardware always.
It's also the Intel-Microsoft cartel trying an end run around anti-trust laws to lock out competitive operating systems.
With how much straight SSD prices have dropped over the past few years, I don't even really see much need for a hybrid drive. In 2011 I bought a 60gb ssd for $95 ($1.58/gb). Today, I can buy a better performing 500gb ssd for $350 ($0.7/gb).
No, mine has all caches disabled. I desoldered the L2 and L3 caches from my CPU to make it overclock better, and I rerouted the memory controllers to only process newly created data. All other data is read/written in real-time directly from the drives.
Even if I ran windows I can't see having a driver for my hard drive. It should just work no matter what OS I am running. Sad and stupid. That's okay though as for me I don't think the hybrid is the way to go. SSD for the OS and external platter type for storage. Like most compromises this seems like the worst of both worlds.
Yeah, a drive that depends on any kind of OS besides the bare metal firmware on the board to which it is attached makes me uneasy. There are just so many more answers to the "what could possibly go wrong" question.
... whatever
Similar question: Which would you rather have: software RAID or hardware RAID? On Linux, software RAID is usually faster, cheaper, more reliable, less buggy & fuller featured.
So yes, I'd prefer the drivers in my operating system rather than buried in some inaccessible firmware somewhere.