Hard Drive of the Future: Ram Drive 403
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."
Good for Mozilla (Score:2)
Re:Good for Mozilla (Score:3, Interesting)
Re:Good for Mozilla (Score:4, Insightful)
Tim
Re:Good for Mozilla (Score:3, Insightful)
Except that you can have memory from here to the moon, yet Windows and various programs running on it will still insist on using disk-based virtual memory anyhow. With XP, setting the pagefile to 0 MB for all drives tends to work for awhile, and through several reboots, but then suddenly Windows will pick a drive and make a 1.5G (the same as the physical memory in my box) pagefile there, without telling me. It only does that if I had it at 0. If I have set some other value, like 512, that will stick. My system has over a gig physical free most of the time, yet still has about 150MB or so allocated as paged. This device turns that stupid problem into nothing, voila! I want it bootable before I will buy one, but I can't wait to have one and point all my apps' temp folders at it, like Cool Edit and such, that would be mega-sweet. Getting to set a nice big pagefile on it as well would be a nice bonus, as Windows could leave me the hell alone about such issues and I wouldn't care that it was being used needlessly.
Re:Good for Mozilla (Score:3, Interesting)
You wouldn't be so kind as to reply with a link to said software ram drive?
I used this trick on my PowerMac 7100 back in the day, having loaded it up with 136MB ram, an insane amount for 1996... I used to run Marathon off the built-in System 7.5 software ramdisk.
External Power Cord!?! (Score:5, Insightful)
Thanks, but no thanks, I'll stick with mah good ole Winchester disks.
Re:External Power Cord!?! (Score:3, Insightful)
The first thing that I thought of when I read the headline after, "hmm, interesting," was, "What?? RAM for storing data?"
I've had problems enough with hard drives crashing and losing data without having to worry about having a power outage and losing everything. A UPS is a good idea for servers, and perhaps in some other special incidences too, but I wouldn't want to be tied down to having one. The electricity to my house is rarely constant, and lights flicker all the time due to lackluster electrical jobs.
For me at least, 2 GB is not nearly enough to store all of my data anyway. If they find a way to assure me that I won't lose my data, and increase the size of the drive, then I may just opt for the enhanced speed. Until then, I'll stick with my current drive.
GOOD! (Score:5, Insightful)
Re:GOOD! (Score:2, Insightful)
POWER SUPPLY (Score:3, Informative)
alternative - diskless clients (Score:2, Offtopic)
1 : file server - all it does is serve files and does backups to WORM. HD Crash only loses todays changes.
2 : auth server - boots from the file server and issues authentication. crash - np reboot it and off you go
3 : cpu server - runs the programs, if it crashes then so what, only data in it's memory will be corrupt, the file server will not have crashed
4 : terminals - bootstrap from a floppy/cdrom/localhd to get authed and then into booting from the file server [or run a windows/bsd/linux client]
One can then add new nodes for redundancy and scale. Local terminals can have local storage if desired
Why this beats a traditional ram drive. (Score:4, Informative)
Re:Why this beats a traditional ram drive. (Score:3, Insightful)
All we need is motherboards that accept more then a gig or two of memory.
Re:Why this beats a traditional ram drive. (Score:3, Insightful)
Try moving to another machine with 2GB still alive on this thing...
Although a really good application for this would be that guy running the game cluster - or any game for that matter.
Run the whole game in the ram drive, everything, including the movies. Talk about speed.
Not practical (Score:4, Insightful)
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.
Re:Not practical (Score:3, Insightful)
Yes, but then you have other issues -- heat, noise, and moving parts. Hard drives are far more prone to hardware failure than RAM is.
Re:Not practical (Score:2)
Re:Not practical (Score:3, Insightful)
OTOH, if you have such large memory requirements you'd probably be using some serious 64-bit hardware and not Intel-based toys.
Re:Not practical (Score:2)
Re:Not practical (Score:4, Informative)
There was even a feature called 'matched memory cycles' in the very early machines where the MCA bus would be temporarily underclocked when accessing memory so that it could work synchronously (cutting some wait states). But then the increasing speed of RAM and the fairly constant bus speed (MCA was 32 bits wide at 10MHz, standard PCI not that much better at 33MHz, while RAM access times have gone down hugely from 85ns to goodness knows what) made the idea look silly, and IBM abandonded MCA-bus memory cards for its second-generation models in 1992 or so. Nowadays you could never get away with using something so slow as the PCI bus for 'memory', so it has to be marketed as 'RAM disk'.
Re:Not practical (Score:3, Interesting)
Re:Not practical (Score:3, Interesting)
1. DRAM drives suffer no penalty to random i/o workloads while disks even in RAID configurations do suffer penalties.
2. DRAM drives export a larger addressable cache area, extending main memory. Throw a couple of these 4 GB modules into your server, and you have essentially extended the cachable address space beyond the 4GB limit of 32-bit CPUs to 16GBs + 4 GB of main memory. For web farm servers this is a nice feature that can be cost effective.
However, in no way should DRAM disks be confused with real drives, where persistence of data is truely important. For example, most RAM drives don't even bother with an external power cable.
Sustained Performance vs. Latency (Score:5, Insightful)
The fundamental problem of "power is lost" can be solved easily by adding a battery on the drive.
Re:Sustained Performance vs. Latency (Score:3, Insightful)
Isn't that "fundamental problem" already solved by plugging any important computer into a UPS? I think we can safely assume that anyone spending $3,000 on a RAM drive would consider their computer important enough to be on a UPS into which, presumably, this device would also be plugged.
What's new? (Score:5, Interesting)
Fundamentally, you're always better just to use caching. Essentially, this amounts to a 2GB dedicated disk cache, except that the power supply ensures that the contents survive boots (though I don't know how it would do in a power failure). Anyway, how often do people reboot their machines nowadays? Stuff stays in my computer's cache for months at a time.
So, why not just add the 2GB to your main RAM? Then the OS could use it as a disk cache if it were so inclined (and you'd be right where you are with a ramdrive) or else the OS could use it as actual RAM if you needed it.
In short, RAM is just like a ramdrive except more flexible.
Re:What's new? (Score:2)
Re:What's new? (Score:2)
Some people can't afford ($) not to reboot (Score:5, Funny)
Anyway, how often do people reboot their machines nowadays?
I'll answer the related question, "why would anybody need to reboot a computer?"
Some slashdot readers are lucky enough to live and work in an environment that primarily uses BSD or Linux. But unlike some slashdot readers, I, Damian Yerrick, live and work in an environment that primarily uses Microsoft Windows. Therefore, I have to use Microsoft Windows.
Some slashdot readers are lucky enough to be able to afford personal copies of PC virtualization software such as VMware, so that they can run other operating systems within a window on their computer. But unlike some slashdot readers, I, Damian Yerrick, can't afford a VMware license. Therefore, I must run Microsoft Windows on the bare hardware, and if I want to run an operating system other than Microsoft Windows, I must reboot my computer to access it.
Some slashdot readers are lucky enough to be able to afford to buy additional hardware to shield their other computer from exploits of newly discovered vulnerabilities in its operating system. But unlike some slashdot readers, I, Damian Yerrick, can't afford a second motherboard, CPU, case, and keyboard on which to run BSD firewall software [closedbsd.org]. Therefore, if I want to keep my computer connected to the network, I must keep my computer updated with patches from Microsoft Windows Update. Those patches often require a reboot of the computer.
Therefore, I, Damian Yerrick, cannot afford to own a computer system that does not have to be rebooted.
Re:What's new? (Score:2, Informative)
1. Random I/O patterns do not benefit from caching.
2. Latency, it takes time to fill the cache which from a disk is on the order of ms.
Caching for I/O on random applications is only good if your cache is larger than your access pattern.
Latency for most applications has a larger impact on performance than IOP/s and MB/s. RAM drives have extremely low latencies, so for some appliations it's better.
Can I use it for swap? (Score:5, Funny)
How This Works... Neat Facts (Score:4, Interesting)
Ram = Fast
Cache = faster ram
On Board Cache = faster
1. Processors used to not have a quick way to get to ram so cache was created (faster and expensive ram) and put on a chip.
2. Cache proved to be too expensive so they put it off the chips (pII)'s. Celereon's even took off some of the Cache.
3. Now that ram drives will be created, it's just another link in the chain to the HD.
now it'll be:
HD->Ramdrive->Ram->off chip cache->onboard cache
Each one of those levels cost more as you move to the right. This just puts another link in the chain.
Re:How This Works... Neat Facts (Score:4, Interesting)
Each one of those levels cost more as you move to the right. This just puts another link in the chain.
Sure about that? For the price of the Ramdrive, I could easily get 2GB of DDR. Hell, for the price of the Ramdrive I could get a motherboard that supported 64GB and fill a moderate chunk of it. That thing has lower speed and greater access time than main memory and costs more, so just using RAM as disk cache would appear to be more useful under the majority of circumstances.
4.7 GB of DDR for $37 (Score:2, Funny)
For the price of the Ramdrive, I could easily get 2GB of DDR
I can get 4.7 GB of DDR for $36.94 [yahoo.com].
for the price of the Ramdrive I could get a motherboard that supported 64GB and fill a moderate chunk of it
If your operating system crashes, what happens? If your OS publisher pushes out a "security update" and asks you to restart your computer, what happens? If you lose power, will your UPS be able to power your motherboard for as long as it can power an external RAM drive?
Re:4.7 GB of DDR for $37 (Score:2)
Using the RAM as disk cache, within about 30 seconds of data ending up there it ought to end up on disk.
Re:How This Works... Neat Facts (Score:3, Informative)
Not limited to 2 GB (Score:5, Informative)
RAM disk vs RAM drive (Score:3, Informative)
I know this article doesn't exactly seem to be chock full of information, but the comments can at least be intelligent.
This is different from using a RAM disk and just using RAM for a disk drive. A RAM drive can actually store information - which is something that RAM disks, which aren't really storage devices at all, cannot do.
This even means you can store stuff and it's still gonna be there when you reboot. Although, granted, this isn't exactly new technology. I remember talking with a company at Internet World probably 6 or 7 years ago that sold these things to big companies with deep wallets.
Stupid Question (Score:2)
Question is valid (Score:2)
But practically, it's no use. Areas that come in mind, already have a better solution than this:
- Games: you're better off buying system RAM (perhaps even creating a software RAM disk), because it's cheaper and about 10x faster than PCI. The guy in the review was mumbling about virtual memory, which is just incompetence really (because you don't need VM as long as you have enough main memory)
- High transaction servers: servers need more storage space than that. And given the high risk of losing data in case of a power outage, this medium is totally unusable.
- Graphics: essentially the same as in games, just buy more system memory. There is no benefit in having this drive that is also quite small.
There is no reason to use such a device. Only if RAM were much cheaper, and if the drive had much more storage, and if the PCI bus were much faster, and if system memory were some kind of other (more expensive, faster) RAM, ONLY THEN would it make sense to use it (and then only if mechanical storage would be far inferior by then).
RAM drives are stupid (Score:2, Interesting)
You can put a couple gigs of RAM on your motherboard, where the bandwidth to the CPU is at least 10x the fastest SCSI interface. Run any modern OS on there, and all of that main memory is going to be used a filesystem cache. Voila: all the benefits of a RAM disk (fast seek, throughput) and none of the drawbacks (no need for a separate disk backup).
If what you want is a TRUE ram disk, i.e. not backed by magnetic storage at all, then you can do this in Linux or FreeBSD by setting aside a chunk of main RAM as a file system. I don't know if you can do that in OSX or Windows...
But a RAM disk on the SCSI bus? What's the point?
Re:RAM drives are stupid (Score:2)
Re:RAM drives are stupid (Score:2)
Re:RAM drives are stupid (Score:5, Interesting)
First off, run ext3 and put all of journal log file on. Poof, now you got a disk that has no latency pently for syncing the data. It will reliable be there when you reboot, so if you crash the log file is still there. You know all those benchmarks that Moshe Bar does where he turns off fsync() so he can push the CPU and memory to it's limits instead of the disk. He wouldn't have to do that so much any more.
Some Oracle DBA's would trade their soul to get Oracle's transaction logs written to something like this. A drive that has no latency is very, very good. No it's not as fast as RAM because it's behind a PCI bus, but in a lot of ways, no latecy permanent storage is the holy grail to a lot of problems.
If filesystems and OS's supported this, it's like getting a very flexible configuration for very high end SCSI cards. You know those really highend SCSI cards that have battery backed up RAM in them? The ones that sit behind that pokey SCSI bus? By putting the no latecy storage out in a place where you can get your hands on it w/ OS tools, you can custom configure it just the way you need it. You can upgrade it, you can add more. You can do a lot of things with this, that are much more flexible then any SCSI card will let you set up.
No they aren't the end all be all of permanent storage, however they have very specific usages, in specific high end situations that make them extremely valuable. If this one doesn't have an internal battery that can hold it's contents for say 400 hours without power, I'm not terribly interested, but as soon as it can do that without external power, I'd pay for it in a heartbeat for the Database servers and the high performance filesystems we run at work. A number of the ext3 people have talked deployment of devices like this will really improve the performance of a number of filesystems.
Kirby
These will never replace mechanical hd's... (Score:2)
However, no one will ever go back to 2GB hard drives for the same prices as a 200GB hard drive, nor will anyone want to go that far back in proportion to Moore's law in the future in exchange for giving up their mechanical hard drives.
Trust me, when we have a terabyte of hard drive space for a few hundred dollars, people will use them -- movies still take up an average of 1GB apiece, and with digital convergence, everyone will want to stockpile them, as well as have every song they've ever wanted to hear stored safely on their hard drive.
Silly (Score:2)
$2,999 for 2 gigs of Ram??? (Score:3, Interesting)
That's an absurd price for what little there is to be gained from this. Clearly the cash would be better spent on a new MB with an extra 2 gig on it - it could be used as a ram disk if you really wanted, or as a cache, or for any number of uses beyond a silly-cone hard drive. Better to be able to deal with the memory as memory than memory pretending to be disk. And for a lot less money.
The future that already was (Score:3, Funny)
Axlon used to make 128 KB Ramdisks, now that was power!
Re:The future that already was (Score:2, Funny)
According to the article... (Score:4, Informative)
Quantum's Rushmore Ultra Solid State Disks (Score:2, Informative)
Extending system RAM... (Score:2, Interesting)
Does anyone know if this maps in as a normal ATA or SCSI controller? Or do you need a special windows only driver?
If linux can recognize it as a normal block device, and I was rich enough to already have 4G of PC2700 on my mobo, then a mkswap/swapon on this device would become beneficial.
Also, can you install more then one in a system?
Re:Extending system RAM... (Score:2, Informative)
Re:Extending system RAM... (Score:2)
Not that I'd buy one, but... (Score:2, Informative)
I'd suggest a better option would be a fast hard disk or RAID appliance with 2GB of cache.
PCI bottleneck (Score:4, Insightful)
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.
More work soulda been put into this card (Score:5, Interesting)
From power off to up and runnig in seconds !
This would be ideal to store an OS, even for a server, and have the HDs configured to copy the os back to the card and reboot in case it fails to boot from the card for some reason
Hook the power source to a ups and you can probably keep the info for more than a week without external power should you need. (i mean, how much juice can this need?)
Missing the Point (Score:5, Interesting)
What if you could boot from this drive? If it were Flash Ram then presumably you could store your operating system on a RAM Drive and get it to boot instantly cutting down on the boring and annoying wait for the computer to start up.
Another drive could be used for storing files and such like (if it were thought to be somewhat dangerous medium to *store*) but in anycase it would be lovely to get instantly booting computers.
In addition, rather than booting, couldn't these drives make possible a kind-of ghost-like save boot-up state. ie Copy into memory very quickly the state of the computer just following boot up. Now that would surely speed up the booting process.
And I know everyone might say, oh that doesn't matter, but even though I use a Powerbook which with OS X stays up almost forever - I *still* need to boot occassionally. And it is *painful* to wait for.
Once it is built into my laptop I will be well happy... I hate chugging drives... and silence is golden
every 20 years (Score:2)
People make these boards whenever the amount of RAM the processor can address becomes small compared to what you can afford, people start putting RAM into RAM disk drives.
However, nearly $3000 for 2G of RAM seems excessive no matter what.
Security (Score:5, Interesting)
Re:Security (Score:3, Informative)
Cache should be expandable on hard drives (Score:4, Insightful)
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?
Swap space?? (Score:3, Interesting)
Re:Swap space?? (Score:2, Insightful)
Another example of military technology trickle dow (Score:5, Interesting)
Most modern Fighter jets use ramdrives exclusively because the high-G manuvers, shaking, ect would cause a normal drives heads to go smashing into the platters. I know the B2-stealth has some, so does the F-16.
When you're the goverment, and you want reliable killing machines, 250k for a 250meg ram drive back in 1987 isn't even an afterthought. It's a requirement. Now that it's dirt cheap to produce memory, it can finally trickle down in price enough to have become feasable for a civilian to afford one.
I know originally the early drives were used to hold map data for the HUD, which was basically just the data gained from our digital elevation modeling sattelites launched in the 80's. Given the advances in 3d modeling and sattelite map aquisition, I would guess whatever system they're using today probably contains terrabytes of map data.
I'm sure the old green vector graphic huds have been replaced with something a lot better to utilize the new data too. I'd suspect that in the actual control area there must be a LCD display, much like what you see on a modern 737.
It must be one helluva video game for them pilots
PCI Problems (Score:3, Insightful)
You could easily smash the performance with a little U160 RAID on a 64 bit pci controller, and perhaps even with a single drive, though seek time would hurt a bit. At least it'd cost you a hell of a lot less.
It's not battery backed either, which is pretty useless for anything this might need to do. Heck, without battery backup, it proabbly can't even survive a reboot to get that precious data back after a system crash!
This reeks of an EE or Embedded Systems course assignment. It's barely a real product.
High resolution video (Score:2)
Solid State Drive (Score:5, Interesting)
The nice thing is that they can drive as many reads/writes as you can get out of the SCSI channel. Seek time isn't a factor at all. We're talking disk performance through the roof here! There are also UltraSCSI and other types that'll go even faster. But the only real limitation is the link between the drive and the computer.
Still, the data rate doesn't approach what this PCI based solution has going. But what I use is a more 'enterprise' solution. You've got internal battery backup and disk backup. If the unit is off the mains, the battery kicks in. After 30 minutes, it stops all IO, dumps to disk, and shuts off. When power is restored, it loads back in from disk.
This PCI solution is way cheaper than the external drives that I've used. Just it doesn't appear to have the reliability... or the commodity standards that'll let it hook up to just about any type of system. Still, quite neat!
I remember back... (Score:2)
Some of the Tandy 1000 series has MS-DOS 3.3 placed in a ROM drive.
Shortly after that a company out in Californa test marketed a bootable ISA card that had Windows 3.1 and a small ramdrive. At the local Sears it was billed as being updatable to Windows 4.0 when it came out[Insert laughter here].
The device was unstable because it didn't use Flash memory. The RAM they did use ate power like you wouldn't believe. Thus the battery life was short and you would have to reinstall your personalized setting.
in the car (Score:2)
I don't understand why RAM drives are overpriced (Score:2)
Obviously it's not good if you buy a stick of RAM for your PC and 100K out of 256Meg don't work, but for an HD-like application, where you have a map of 'bad sectors', it's not a problem.
Heck, considering that nowadays 'bad' RAM chips are basically thrown away, I could see a 10gig model (external maybe, due to space constraints) going for half of what this 2gig model costs.
Spending $2000 on 2 gigs of ram seems really gouging of the early adopters.
Useful as the ext3 journal (Score:5, Informative)
While profiling a high-volume qmail server with fast mirrored drives, I noticed that I could get at least an order of magnitude sustained mail throughput by eliminating the fsync() system call, which essentially forces the disk subsystem to stop whatever else its doing and get a few specific blocks all the way onto disk. You can't run it in production this way, as the SMTP RFC specifies that the mail must be actually on disk before the server can claim that its done.
The problem is that magnetic-media drives can only seek a few hundred times per second. Regardless of their claimed sustained throughput, if you are writing a bunch of small files to disk, you are completely dependent on the seek time of the drive.
But mounting a magnetic-media-based ext3 with data=journal and the journal on an NVRAM block device would essentially use this as a trusted write-cache. Linux will return from the fsync() system call as soon as the data is in the journal, which could happen instantly on an NVRAM disk as there is no seek time. It then reads from the journal in its spare time, sorts it to minimize seeks, and writes the data out to disk.
I suspect that this should offer roughly the same speed as eliminating the fsync()s entirely.
I was looking into ordering a similar product to test this. I found:
Been there, done that, got the T-shirt (Score:3, Interesting)
The point is that with the drives that I have used (SCSI-U2W through fibre channel) is that they used good old fashioned interfaces which meant that they were plug compatible with older hardware.
Blah that's silly (Score:3, Interesting)
If you're willing to fork out the money, there's several manufacturers who have been puttng out genuine static ram drives for a while. They have microsecond access times, sizes up to 80-ish GB last I saw, IDE and SCSI interfaces, and can have sustained bandwidths limited only by the bus speed. They also consume less power, generate less heat, and don't fail as often because there's no moving parts. They solved the limited write cycle problem by having the drive logic remap blocks of data to spread the write wear around the drive.
FOr a bleeding edge example, check out E-DISK's soon-to-be-available Ultra320 drive (they're released other similar drives before, just not at this performance level):
Size: up to 155GB
Access time: 33-48 us (microsecond)
IOPS: 9500 - 50000 per second
Burst data rate: 320 MBps
Sustained data rate: 230 MBps
Full Erase (Security feature, press a button): around 26 seconds.
ECC error correction, MTBF around 2 million hours, 10 year data integrity.
Write life-cycle of in excess of 100 years at 100 GB of writes per day.
This is new? (Score:3, Interesting)
I asked that man what would happen if the power was lost. He said that the box had a battery and a hard drive of the RAM capacity inside. If the power was lost, the battery would power it long enough to write all the data to the hard drive. I asked what the advantage was over a regular hard drive. He said access speed and no moving parts. Ok, great benefit, but it didn't seem the value was there for 10x the cost of a drive itself. Anyone remember this?
I started waiting years ago for someone to come up with a board where I could plug in all those 256k, 30 pin SIMMs that we took out of the Mac Plus' when we upgraded them to 4 MB of memory so I could use them for storage. Never happened (that I know). Now I'm waiting for the same thing for this ever mounting stack of 4, 8, 16 and even 32MB, 72 pin SIMMs.
Where is the real innovation? I mean, our favored OS here can run well on all this old hardware - 486 and the like, but where are the little trinkets for us cheap SOB's like me? I just want a 5 1/4 external case with a 25 pin D connector that will connect to my SCSI card. The board inside should have jillions of 72 pin SIMM sockets (in pairs is ok, multi-level board is ok) and a connector for an old ATAPI 2 or 3 Gig laptop drive. The case should have room for a little battery to do what that really expensive drive could do years ago to backup in case of a power failure. Hell, I'd even pay 50 bucks or so for it. Any takers?
I'm not an EE so I'm not up to making it myself, but someone out there would consider it a fun project...
You know, reuse, recycle, make the world a better place. I don't want to have to throw out all this memory or sell it for a quarter a stick. I guess I could use the dremel tool, drill little holes in them and make geek earrings, but I don't wanna have to do that either.
If anyone has any ideas, lemme know.
BTW, no need to call me a cheap SOB luddite, I already did that...
Pricing Sucks (Score:4, Insightful)
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.
*ONLY* a factor of TWO??? (Score:3, Interesting)
Does anyone else read that as an endorsement of the usefulness of buffering and other performance technologies applied to disk drives?
I'd imagine that applications in ruggedized systems or devices that need to be exposed to significant acceleration or zero gravity will be more important than the speed increases, but, I'm quite surprised that a 15krpm SCSI drive comes this close to a RAM device.
One other benchmark that would be useful, would be to compare the speed to the normal RAM in a given system. Is it a net gain to have your RAM on an expansion card? Or would a RAM drive on the regular memory space be better? Is this more or less expensive than system RAM?
Not for home users... (Score:4, Informative)
Alternatively, as at least one other poster has already mentioned - if you use a journalling filesystem like ext3 or rieserfs, then putting the journal on a seperate solid-state disk is a huge performance gain.
Underachievers! (Score:4, Insightful)
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.
Re:x10^2?! (Score:3, Informative)
Manufacturer: Cenatek
Web site: Product Information
Price (MSRP): $2,999 (as tested)
Release Date: Available Now
Re:x10^2?! (Score:4, Funny)
Re:x10^2?! (Score:2, Informative)
i hope they put some sweet memory in there...
Re:x10^2?! (Score:2)
Re:Huh? (Score:4, Insightful)
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.
Plz read the article (Score:2)
The test used sisoft adn HD Tach for testing.
The speed is limited because of the pci interface, that is as fast as the pci was designed to work at.
Re:Huh? (Score:5, Informative)
Actually, the author of the article made it disk bound, by forcing Photoshop to go into swap space with an image much larger than the available memory.
And you missed the HD testing pictures, measuring high throughput (sp?) and unbelievable low latency.
Yes, but this one ... (Score:5, Informative)
It has an external supply that keeps the card powered.
And i believe this is the whole point of this card, its pretty much useless otherwise.
Also the xfer speeds are limited to PCI (66mhz) speeds, that is why "its only" 2x as fast as a U160 scsi.
Re:Yes, but this one ... (Score:2)
Fair enough, but.. (Score:2, Interesting)
Most Slashdotters are the type who leave their PCs on 24/7 anyway, and run relatively stable operating systems. And if the power cuts out, you're going to lose the RAM drive anyway.
I can see the use of this RAM drive in video setups or on DVD encoding/production desks, but for regular Joe (or even a Slashdot user)? No.
Too true, (Score:2)
I also think that the only application of this is for volatile info that needs massive disk i/o
I believe all programs would benefit from 4gb of ram instead of a 4gb ramdrive, and i specially disliked the fact that altho you can buy a card wihout memory you can only use it with the ammount you bought it for (its "bios" is locked to that memsize) so you can't just go on adding mem.
It's RANDOM I/O that's implortant (Score:3)
Think of applications that need to randomly access the drive. Think web servers, caching proxies, databases, etc. We had a custom app that needed to write to around 40,000 files simultainiously, and read from them randomly. The only feasable solution was a rather large RAM drive system. The one we used was external, had it's own hard drive for backing up the image, UPS, etc., hooked up to the normal SCSI bus, and cost around $12K for a 2G box (this was a number of years ago when RAM was much more expensive).
Nice thing was NO DRIVERS. It was a SCSI drive to the OS. You could boot off it if you wanted to.
Soliddata.com in case you are wondering.
ups (Score:2)
But i still would not put into this important information that i didnt have on another medium sowmehere else.
Re:What's the point? (Score:2, Funny)
You must not be a geek if you need to ever ask that.
>You can already create RAM drives using the memory you have in your machine. You don't need a dedicated unit to do it.
Yes you can, but can you plug those ram drives into a UPS and keep the contents between reboots?
>Heck, I could create meagre RAM drives on my 640KB Amstrad PC1640 (8086).
So?
>Why not just fit your PC out with 4GB of fast DDR RAM and do it that way? That memory would be far cheaper than this card.
What if I want 4gigs of ram AND a ramdrive? I don't, one gig of ram is enough...
Personally I don't get why people always expect products to have a really necessary use
Re:What's the point? (Score:4, Insightful)
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.
Re:What's the point? (Score:2)
This is persistent storage (as long as you have a UPS on the external power sonnection), and would be great to use for the journal of your filesystem, making it act like a fast write cache that was persistent. Would allow more write combining and such before being written out to the real hard drive.
As you mention, more RAM as a cache pretty much would make up for any other use of this I can think of.
Re:Of the future? (Score:3, Insightful)
Once you do this then ALL heads will be able to read or write simultaneously (in parallel) rather than one at a time as they do now.
Only question is -- how long till they decide to go for it.
Platter-level RAID (Score:2, Insightful)
It has been tried in the past, but the problem was that the heads would get slightly misaligned in time and you'd have to reformat too often.
To solve rotational misalignment in a platter-level RAID system, just treat the binary stream coming from each head assembly as a separately clocked serial stream, and combine them in the controller.
It's also straightforward to solve radial misalignment, that is, when one of the heads is slightly too far from the hub or too close to the hub. While the drive is idle, non-destructively reformat the disk continuously, reading an entire cylinder/sector pair head by head and then writing it all at once.
Re:Platter-level RAID (Score:3, Interesting)
Re:Of the future? (Score:2)
Re:Swap FIle (Score:3, Informative)
I would buy extra ram instead of this rocketdrive. The bandwidth of my system ram is 2.1GB/s. This rocketdrive benchmarks at 78MB/s.
If i were you i would wait for MRAM (Score:3, Interesting)