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Hard Drive of the Future: Ram Drive
benzick writes "3d Retreat has posted a hands on look at a 2gig ram drive called the Rocket Drive. Article blurb: Overall the rocket drive is the best in I/O performance I have seen. It outperforms U160 SCSI drives by almost a factor of two. Yet there are some drawbacks to the Rocket drive, foremost is the price, although listed at the end of the review is some alternative pricing options to make it less expensive. And the rocket drive can not act as a boot drive. Also, if you have some extra money to spend, you can use multiple rocket drives in parallel."
It's another bullshit "hardware site" test.
The "benchmark" was a Photoshop filter on an image. It was twice as fast as with the SCSI disk.
This tells you very little about the relative performance of the drives since image processing is typically not disk bound.
And if someone trips over the cable, there goes your 2 gigs of data!
Thanks, but no thanks, I'll stick with mah good ole Winchester disks.
The hard drive is some ancient technology that is the *easily* #1 cause of all computer failures. Other than the cooling fans, they're the last moving parts, and the most critical ones too... A fan dying may cook your computer, but a hard drive kills your *data*. It's high time that something came along to replace those damn things. I'm typing this on my PC with a 2 drive RAID because I can't afford downtime or data loss. That really shouldn't be necessary any more. Bring on the alternatives!
1. A DRAM "drive" suffers the fundemental problem that if the "external" power source is lost, you lose everything on the drive.
2. 80-100 MB/sec sustained performance is nothing to write home about for DRAM performance. A RAID 0 stripe across 2 ATA drives could give you this same performance for about 1/4 the price without the power issue.
Although its a long way off, MRAM offers a much more promissing application in the area of high speed RAM drives.
Someone you trust is one of us.
The article mentions that multiple RocketDrives could be used in parallel. That would seem only to be practical on 64-bit PCI buses. One RocketDrive transfers 80MB/s, which is close to the maximum sustained bandwidth for 32-bit 33MHz PCI. 132MB/s is the burst bandwidth, and cannot be sustained for very long.
In fact, I would think this drive would interfere with other devices that rely on the PCI bus. I doubt you could get 100Mbps (~12.5MB/s) on the same PCI bus.
"Sustained performance" is only a practical measure in a few uses (eg: multimedia). For most other things, latency (ie: seek times) has a far greater impact on performance. Even the fastest harddrives have seek times measured in milliseconds. With DRAM we're talking about nanoseconds.
The fundamental problem of "power is lost" can be solved easily by adding a battery on the drive.
Okay... I'll do the stupid things first, then you shy people follow.
[Zappa]
This is just sad...
3,000 dollars for something that has 2 gig of ram. I could get 2 gig of ram for a fraction of that amount... In fact, for the speed its giving, I could fill the thing up with sdram or edo ram...
This is something I could imagine being useful with my hard drive... Why don't they make a standard plugin for hard drives... Make it where you can add cache directly to the hard drive.
But wouldn't it be better to just have RAM instead of this?
Not if you're going to go over 4 gig. You'd then need a 64 bit solution for that... If, on the other hand, you could add MAJOR amounts of cache to your hard drive, it wouldn't matter if you only had 4 gig of actual memory. You could run IA-32 as long as you like. You could have potentially gigantic databases without worrying as much about disk thrashing...
It's going to be potentially a long time until a 64 bit winner in the PC world is declared... As time goes on, something like this may actually be viable. And as memory prices go down, we're going to be seeing a lot more 4 gig systems around...
Or am I on crack?
/^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$/i
Furthermore, RAM drives are really meant for servers. Such a server will most likely use a fast internal memory (like RAMBUS) and cheaper, slower & much larger SDRAM 100 for the RAM drive.
The Raven.
The Raven
Putting your swapfile on this doesn't make much sense. You'd be buying memory, putting it in a special card that makes the memory act like a hard drive, then making that hard drive act like memory. It would be cheaper to just buy more regular memory.
Tim
Omnia vestra castrorum habetur nobis.
This is potentially interesting, but there are several problems:
1. The pricing model sucks. The entry price of $399 is too high for a card with one chip and four DIMM sockets. And that only supports 512MB. To go to 1GB, 2GB or 4GB you have to pay hundreds of dollars more - even though the only change is a BIOS setting.
2. The RAM pricing is absurd. These guys need a reality check, pronto.
3. The board takes standard PC133 NON-PARITY RAM. No way in Hell would I trust my data to something like that. Honestly, this is just plain stupid. The board is too expensive for the home market and no-one sane is going to put non-ECC memory in a server.
[As a side point: Even using standard DIMMs, you could do some sort of block-ECC at the driver level (or in the controller chip) and use the fourth DIMM as a parity device to recover from on failures, like RAID-3. Alternately, you could treat each DIMM as a 48-bit device and use the remainder for ECC and Chipkill. There's nothing on Cenatek's site to suggest they do anything like this, though.]
There's a few other things that annoy me: the lack of specifications (while they have a list of approved memory modules, they point-blank refuse to provide the required memory specs on their support forum). Also, the board appears to require four identical DIMMs, which is a royal pain in the bum. Expandability? What's that? Low entry cost? Don't got one of those either.
So this board appears to be worthless for its target market and overpriced for anything else.
One-word review: Sucks.
Score: 3/10.
Memory is absurdly cheap, and a properly thought out board (even one that implements the ECC in software) at the right price has a market waiting. I know a lot of people doing embedded Telco apps would love something like this. This card isn't it.
The Platypus card is also over-priced, but it does support (indeed, requires) ECC, and also goes up to 8GB.
I don't get it.. let's assume, in the name of generosity, that U160 actually pushes 160mb constantly. Then the rocket drive pushes 320mb constantly. Now we've got PC3200 ddr ram that can theoretically push 3.2 gigs per second, while this rocket drive only does a tenth of that.
What's the damn point ? It has to go through some sort of slow-ass bus anyways.. it's not like it has precisely timed local access to the northbridge, like traditional ram.
It would be better for motherboard (and chipset) makers to accomodate buckets of ram sticks, so we can allocate a real RAM disk using 8 or 16 sticks of 512mb/1gb ddr.
-Billco, Fnarg.com