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RAM Disk Puts New Spin On the SSD
theraindog writes "Although the solid-state storage market is currently dominated by flash-based devices, you can also build an SSD out of standard system memory modules. Hardware-based RAM disks tend to be prohibitively expensive, but ACard has built an affordable one that supports up to 64GB of standard DDR2 memory and features dual Serial ATA ports to improve performance with RAID configurations. And it's driver-free and OS-independent, too. The Tech Report's in-depth review of the ANS-9010 RAM disk pits it against the fastest SSDs around and nicely illustrates the drive's staggering performance potential with multitasking and multi-user loads. However, it also highlights the device's shortcomings, including the fact that SSDs are more practical for most applications."
so, this is just as worthless as Gigabyte's i-RAM.
It seems that with a little firmware it could be coaxed to do some content addressability. Considering that it is 10x faster inside than the peak of the SATA interface. It seems to me that there is a lot of potential. I always liked the ram disks when they were popular ISA cards and this could be the thing that could use the full power of USB 4.0 [sic]. Applications could be changed to take advantage of this speed. If lists and SQL databases could be sorted on the drive without CPU overhead, it could be very useful.
My university used RAM disks back in the day - it was the only way to get decent performance on older machines. The computers didn't even have hard disks in. My brother (who went to the same university) has a story where he sped up his large FORTRAN compiles by a factor of 10 just by working out how to use the RAMDisk (which was only ever used by the PXE-style boot procedure and then hidden from the OS) for his own purposes and people couldn't work out how he was doing it because he still took stuff home and brought it in on floppy. This is a nice hark back to those times.
The killer, however, is the price... the price of a PC, basically, before you add the RAM. If you're REALLY serious, you'll have machines that can just take the extra RAM directly and do this in software. If you're not willing to pay that much, well, nothing will work for you but a few bits of extra RAM and a fast SSD for the same price won't go amiss. However, if you occupy the middle ground... this still doesn't seem worth the effort. It'd be cheaper to just buy an SSD, some extra RAM for cache and maybe even a cheap PC to throw it all in (if NanoITX supported 8Gig chips, this device could almost be made obsolete overnight).
The interconnect too - yes, it emulates a SATA drive but it emulates two as well and fails to do anything significant with them. So you'd need a RAID0 setup, with independent SATA setup, and an expensive device, with lots of even more expensive RAM just to be a fraction of a second quicker than an off-the-shelf SSD in the same machine. The people for whom it's worth it won't want to be bothered with all this.
The CF Backup feature is fantastic. I love the idea. But 20 minutes is a long time to wait if the battery is only four hours worth when it's brand new (four hours? At least 24 would have been useful and given you a chance to actually do something with it). You would want to be backing up anything this thing held anyway, so you don't really gain anything because the CF is the most inconvenient backup because of its manual nature.
I can't see a situation where 64Gb of fast storage is worth that amount of money + time + hassle + 64Gb of RAM + potential firmware problems + interface cabling + ... The bottlenecks in anything serious are going to be elsewhere.
This brings up an interesting idea.
What if the ramdisk function was moved into the motherboard chipset? This would achieve 2 things:
1. It would dramatically cut the cost of a ramdisk. I.e. The cost of the entire motherboard might go up by $5 or so.
2. It would eliminate that SATA bottleneck, allowing ramdisk to run at full RAM speed.
If you then figure out a way to have this data loaded to the ramdisk from a hard drive at poweron (or get realy clever and mount a flash chip on or near each DIMM which takes a backup of that DIMM, just before powerdown.
--= Isn't it surprising how badly I spell ?
The real question that is not being answered here is why does a 32 GB SD card cost $25 but a 64 GB SATA hard drive cost $800?
A 32GB SDHC card right now on Newegg (in-stock) is a minimum of $72. I don't know where you got the $25 number (sure, in another year it will be that cheap). As another poster mentioned, Newegg has 32GB SSDs available for the same price range.
Why can't the technology that makes SD cards so cheap make cheap SATA hard drives as well?
It already has. The first SSDs on the market used single-level cell (SLC) flash, while the inexpensive SD cards and mp3 players you see everywhere use multi-level cell (MLC) flash. The difference is how densely you can pack the data, and it makes a huge difference in price.
To put it simply: SLC flash is faster, lower-power, and more reliable than MLC flash, but also more expensive (at same capacity) than MLC flash.
The reason the first SSDs used SLC flash is because new technologies have to convince people to take the plunge: people/companies are usually willing to pay significantly more for something that is much faster and more reliable. Early adpoters might have given SSDs the cold shoulder if the first wave of drives reduced capacity and performance in-order to be more cost-competitive with existing storage.
Now that SSDs are firmly off-the-ground, manufacturers are offering all sorts of devices, including cut-rate drives using MLC flash, so the prices at the low-end have dropped like a rock.
Man is the animal that laughs.
And occasionally whores for Karma.
That's not what I want. I don't want to have to buy the fastest, most expensive RAM available just to use as a RAM disk. I'd prefer cheaper RAM, maybe two or three generations old, that I can get in massive quantities.
Except that you can't get two or three gen old RAM in massive quantities. At least, not for as cheap as the new stuff. See for yourself: 1 GB of PC 133 RAM is more expensive than 1 GB of DDR or DDR2 RAM. There's a very short window of "cheaper" just behind the bleeding edge that's cheaper than the very latest (DDR3) but new motherboards support this type of RAM too, negating the "two or three gen old" situation that you state.
Most people think that the older the technology, the cheaper it gets. But this is only true for a very small time window, at which point the older technology gets phased out (not profitable, anymore) at which point it becomes a "niche" marketplace with very low volume and very high prices.
Example: A PC-133 RAM stick needed to keep a $12,000 vertical-market weaving loom operational, where the cost of the additional RAM pales compared to the cost of the entire integrated system. If you need that extra 512k of RAM in your $12,000 loom, paying $100 for it isn't such a bad deal.
But there aren't many people stuck with $12,000 looms, so the price of the older technology skyrockets until it's simply not available anymore. (Ever try buying a *NEW* Cx 6x86 processor in the last year or so?)
I have no problem with your religion until you decide it's reason to deprive others of the truth.