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."

Comments

I RTFA and now speculate

[moteyalpha]

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.

Good idea

[ledow]

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.

Re:What I learned from the article

[Forge]

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.