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OCZ Couples SSD, Mechanical Storage On a PCIe Card
J. Dzhugashvili writes "We've seen some solid-state drives on PCI Express cards before, but OCZ's RevoDrive Hybrid may very well be the first solution to combine solid-state storage and a mechanical hard drive on a single PCI Express x4 card. Using Dataplex caching software from Nvelo, the RevoDrive Hybrid uses its solid-state component (a RAID 0 array of SandForce-based SSDs) as a cache for an onboard mechanical hard drive. The caching scheme is reportedly so effective that "a 5,400-RPM drive can be used without sacrificing much performance," according to The Tech Report's coverage. OCZ hasn't hashed out all of the details yet, but it expects the RevoDrive Hybrid to start at $350 this July. The base configuration should couple 60GB of solid-state storage with a 500GB mechanical drive."
Do anyone remember the old ISA hardcards?
I've never understood why they make those 200 - 300 GB SSD drives, when ~30 GB of SSD cache will hold your operating system and your most frequently used applications. It's not like everything on your hard drive needs to always be immediately available at SSD speeds, and yet recently that's been the only option.
Caching isn't some mysterious arcane technology, why has it taken so long for them to make a hybrid drive like this?
Recently, after reading performance reviews on the Vertex 3, I bought one. The speed is simply amazing! I've been using it as a data-intensive development database server drive. Shortly after buying it, I discovered that there were numerous complaints about the Vertex 2 being unreliable.
To this, I can only say that after about 6 weeks of extremely heavy use as the data partition on a PostgreSQL 8.4 server I've had no issues so far.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
There are at the very least two other solutions that do the same thing, that were out there before this one:
HighPoint RocketHybrid: exactly the same, an expansion card with connectors for one ssd and one hdd.
Intel Smart Response Technology: Software on top of the Z68 chipset that uses an SSD of up to 60GB as cache for a different drive or raid.
I looked into existing hybrid SSDs for notebooks lately and was scared off by piles of negative reviews. Most now are 4 GB flash, 250+ GB mechanical and it intelligently determines what you open most often and transfers it to the flash section. Apparently that causes poor performance in certain circumstances, unpredictable performance in all circumstances, and lots and lots and lots of crashes and blue screens. If they got all that taken care of and upped it from 4 GB to 60 GB this would be a nice solution but for $350 I'd just get a 160GB or bigger SSD! What an insane price point even for a PCI-E version!
Also, the price difference in motherboards is huge. I have a graphics card in PCI-E 1 of course and my board has just one x16 slot. Needing a 2nd 16x or even 8x PCI-E slot means around double the price on average. So if it went from a $90 board to a $180 board, you might as well have just bought an even higher capacity SSD for the same price. It would work with non-graphical computers but with SSDs, quite a few are gaming computers. I think I'm better off getting one of those 400MB/sec+ 32-60 GB SSDs and installing my games on it. Most new ones support that. My boot time would still be crap but my 3D models would skin ultra fast and the load times would be really quick. Now that's a hybrid system.
They seem to want to back ~10% of the storage with SSD. Thats the OS, select files and applications?
Your game/photoshop/browser will load SSD fast, the large video clip last watched 4 months ago may not.
How smart will MS be about fitting the 50 or so gigs of used files and sorting 'todays' work?
Will you hit a part of your 500 gb @ 5,400-RPM sort mid game?
Domestic spying is now "Benign Information Gathering"
OCZ just recently swapped their NAND for cheaper, denser, slower NAND. They didn't even change the model #. When enough complaints came in, they were forced to RMA everyone's drives or face a bait&switch lawsuit.
Actually, all you need to cache is meta-data and small files (say anything less than 100 kB). Anything larger (assuming it is unfragmented) can be streamed from a traditional harddisk at speeds comparable to SSD's anyway.
Large files are almost by definition rarely accessed randomly as they are usually some kind of media (image, music, video).
Also, at today's data density, even traditional harddisks can saturate a link as long as the reads are sequential.
NewsFlash: SSD are much faster than HDD, but much more expensive, so it makes sense to use an SSD to cache HDD content. For some obscure reason (probably the need for something new in Win8); MS refuses to do that (even though they can ReadyBoost off of a USB stick...), so it has fallen to third parties to implement it in software of hardware, even though it should really be the OS doing it.
How it's actually done is of no real import, all are kludges anyway because MS is, once again, letting us down.
The Cloud - because you don't care if your apps and data are up in the air.
You're are correct, SSDs don't have any issues with read/write cycles. But this following line is hilarious;
put your page file on a RAM drive
Think about it. You're talking about creating a virtual hard drive using RAM which is used to store page files that you don't want in RAM.
Just turn your page files off altogether. In this scenario there's no disadvantage to doing so. The total available RAM (real+page file) will be the same either way and you save yourself from going through a completely pointless layer of indirection.
> J. Dzhugashvili writes
That's pretty offensive for a large part of the world population!
Just for the record: Josif (Vissarionovich) Dzhugashvili was the birth name of Stalin, the soviet communist dictator, who was more interested in sending people to the Gulags for hard labor, to give them bad memories, rather than hard drives combined with memory chips. Around 25 million did not return, in total.
Wonder if an austrian painter, Adolphus Shicklgruber will report next time about the new USB 4.0 draft standard or so.
Their HSDL drives have transfer rates of 720mb/s, how about evolving from there instead of regressing?
Grammar nazis are to this community what excrements are to gold.
I'm honestly confused. And still open-minded.
Explain to me why I need this instead of spending that $300 on a 7200 or 10000 rpm drive with two to four times the capacity and far, far more reliability and service life.
Is it just to extend the time I can operate on battery power? A second battery will double my time at far less cost.
I can see the fnords!
with your own hard drive and your own SSD. It'd probably cost less, too. http://bcache.evilpiepirate.org/
Wow! The very high cost of a solid state drive coupled with the power hunger and mechanical constraints of a hard drive. I find it hard to believe that using SSDs as a cache is wise, but I also question if the money couldn't be better spent adding more DDR3 RAM to the processor and letting it cache the drive (with the obvious options and benefits that brings). I think I would just stick with the 2TB drives that I've been buying recently for well under $100 each rather than this overpriced compromise, even if I had a 4x PCIe slot available (which I don't and I expect few who would have an interest in this do).
I'm an American. I love this country and the freedoms that we used to have.
Interesting, indeed. I can't disagree with anything you said.
But back in context: Does this OCZ device do this sort of selective caching? It seems to me that, in order for it to do so, it'd have to be aware of (at least) the filesystem. That's not so far-fetched, given today's low-cost CPUs and FPGAs (we've had various NICs running Linux available for years now, for instance, to wring out the nth degree of latency), but again: Does it do any of this?
Or is it just a somewhat-larger SSD-based multi-gigabyte caching system of the same sort that common and modern operating systems already supply with RAM caching?
Or is it worse? (I suspect this, but without a product, I can't say...)
Kid-proof tablet..
As always, it entirely depends upon what you are doing.
While at home I've got a relatively cheap 30GB SSD purely for game files I needed a pair of striped 240GB SSDs for files that are continuously getting accessed at work by about a dozen people. It's not a real database so an hourly snapshot to spinning disk does the job of redundancy reasonably well. If the SSDs die the snapshot is always in a usable state even if individual files are up to an hour out of date.
The way MS Windows swaps makes perfect sense in some situations but appears utterly braindead in others. That's why some corner cases with things like some games on machines with a lot of memory can actually benefit from doing things that appear to be utterly stupid - eg. virtual drive on ramdisk. Without a page file at all you can find the bugs where there is an assumption that there is a pagefile :(
Maybe MS Windows 7 acts more like a server OS and handles virtual disks in a more sensible way than XP.
On a real server OS I assumed the users wouldn't chew up the 64GB I had on one machine but gave it 8GB of swap anyway. It needed all of that for one task and in hindsight it looks like I should add a resizable swap file in addition to the swap partitions. Once you put something new on a machine everything could change - for instance on an MS Windows machine it could take something as simple as a tabbed web browser to go from the requirement of not needing virtual memory to needing a lot of it.
Depends on how aggressive the cache is. It doesn't need to be very aggressive if it is non-volatile. Say for example you are caching some oft used OS file. With a smart cache controller, it shouldn't be a whole lot different than having two separate drives, one for system, one for apps. Except you dont' have to go out of your way to manage that. Nor does the OS.
So, not that different from the Momentus XT - which is a hard drive with a bunch of SSD as a cache...
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You'd figure with a few gigs of SSD even as much as a silly thumbdrive worth you could get read speeds on par with SSD. SSD are crap for massive amounts of data, for now. Though, I think tying your data to die on a thing with moving parts, vs. and SSD gets the worst of both worlds too. You get the speed of SSD without getting rid of the potential to no longer have the silly things crash.
I'd prefer if people just really understood they are two different technologies and you should have one of each. You should have 20 gigs for your OS of SSD and you should have 2 TB of data for whatever else.
Somebody should invent a form of RAID for drives of radically different sizes and read speeds that just works a bit like stripping but as a cache. Make this silly doohicky here pointless.
It is no longer uncommon to be uncommon.
Where I am I get occasional power weirdness that flickers the lights and panics every UPS into a hard shutdown but everything on mains stays on. You can get it too no matter what part of the world you are in if somebody is using an industrial crane or similar big bit of gear within a kilometre or two. That's after spike filtering etc for the entire site. It's really annoying when the only things that go down are the switches, file servers and phone systems. A UPS is pretty well certain to fail once every three years or so anyway - many properly with plenty of warning but even some from expensive brands just do a battery test, fail it and turn themselves off and that's the first you know that it's time to replace the batteries. That's not how they are supposed to do it according to their manuals and some of the same model may behave properly, but they do it anyway.
Battery backed controller cards save my arse in that situation because the cached writes are still there ready to be done when the power comes back on.
As for redundant power supplies, I have a failed redundant power supply chassis on my desk because the redundant modules are still OK but the non-redundant chassis for them is dead. Everything dies. The OS won't save you completely from hardware failures.
I was burned once. Paid good money 2 or so years back for 2 fairly pricey SSDs. A couple months down the line, halfway full, they started stuttering like failing harddrives or harddrives waking up. It was painful. There were few reviews online at the time of purchase, but when the problems cropped up, I found out that the controllers in them were considered complete crap and that OCZ wouldn't do anything about screwed customers other than replace failing ones with the same exact model even though they had a new one in the works.
Since then, I've stuck with intel and haven't regretted it. While I realize OCZ probably have their stuff together now, I don't look favorably upon companies that are willing to ship obvious crap. (And they must have realized the problem early in testing already.)
But yes, I do love SSDs. Still use HDD for long-term, rarely accessed storage, but for working on? No comparison.
Some files I never want cached, or some dirs.
ie. such as all my mp3s/avi's dont need to be cached.
Liberty freedom are no1, not dicks in suits.
Are motherboards and the PCI connectors going to like the vibration levels of having the drive on the card? I'm not saying it will fail, I just don't know. It's not the normal use case.
Solid state cache: yes. Flash based: no.
Gaming. Most games use some sort of single-file archive for all the textures, meshes, animations, and sounds. With modern games, those are usually 4-10GB. And the access patterns are only rarely sequential. Hence why some gamers invest extra on 10krpm hard drives or (now) SSDs - loading times in some games can be ridiculous otherwise.
Googling i found this;, havent tried, but here it is;
Go to:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\EMDMgmt\[drivekey]
Change:
DeviceStatus to 2
Liberty freedom are no1, not dicks in suits.
when I fill the entire storage space and randomly select files from across the drive to work with.
you had to pick whether to put a half-height 5.25" or a 3.5" in the remaining half of the drive bay
TheRaven64 wrote:
With a hard disk, you didn't really need the second floppy disk.
Unless you wanted to exchange data with other machines using both sizes, or to use applications that used "key disk" copy authentication. Or did they have drives that accepted both 5.25" and 3.5" floppy disks in the era of sub-0.1 GB hard drives?
What is with the SSD hate? Eternal sunshine of the HDD mind? Seriously, SDDs aren't perfect but are usually still salvageable by a restoration firm because the card blows but the memory is intact. I agree they're not entirely reliable and they have shortened lifespan from what people seem to deal with (my 64 GB SSD going on 2 years and working just fine). I would though for $120-150 easily justify an OS boot drive that holds only programs and the OS while having a larger 1TB+ drive for other work. This just combines that into a standardized system which for the price is actually fairly cheap compared to large 64 MB cached 1TB hard drives if you look at the combination cost and the PCI-E x4 speed.
Course this is all relative and real world performance of SATA II is fast enough to handle Win 7 and most other items currently.
You're mostly right, but SSD's have been outstripping platter HDD's in sequential performance for at least a couple of years now; my comparatively ancient and pedestrian OCZ agility could do sequential reads and writes faster than the 150GB raptor it replaced (across the whole "surface"), and random access patterns were already a couple of orders of magnitudes faster. There are still very few SATA discs that can saturate a single 150MB/s connection on a sequential read, whilst SSD's were bandwidth limited to ~270MB/s until 6Gbps SATA arrived earlier this year in the form of new AMD and Intel chipsets (I don't count the 6Gbps marvell SATA controllers cos they're crap).
I picked up a 256GB crucial C300 last year that's currently used as scratch space for video editing - reads at 350MB/s, writes at 270MB/s, to get anywhere near that with platter based hard drives you're already talking spending comparable amounts on just a decent RAID card. Newer drives out this year are already pushing 500MB/s, to say nothing of the PCIe based SSD's.
If you need the space, use platters and a RAID card. If you need the speed, use an SSD. If you need both...
Back OT, this OCZ thing is nothing terribly new, and I suspect its thunder is going to be stolen in the consumer space by Intel's "SRT" (essentially software/driver based use of an SSD as either a read-through or a write-through cache) with a plan jane HDD (doesn't have to be a comparatively weedy 2.5" either) on the backend. Sadly it's windows-only and (stupidly) restricted to only the Z68 chipset at present. Enterprises are already using things like ZFS-with-an-SSD-cache (or some other SAN/NAS with built in flash cache) or, like ourselves, Fusion-IO in between the SAN and our blades.
Anand did a fairly thorough comparison of intel's caching technology here http://www.anandtech.com/print/4337 and I suspect the OCZ card won't be any better performance wise (and don't get me started on OCZ's QA...!). Well worth a read if you're thinking about building a computer in the next six months.
Moderation Total: -1 Troll, +3 Goat
Actually, all you need to cache is meta-data and small files (say anything less than 100 kB).
Are there any file systems that manage this transparently?
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