News Intel, Micron unveil ultra-fast 3D XPoint universal memory

As I understand it, this isn't as fast as D-RAM but is close enough in performance that it could be used as D-RAM if speed isn't as critical. It will be fascinating to see if this ends up in an SSD/Ram common pool of memory in certain low power applications. Would be a great way to make laptops / tablets smaller again if you just had, say, a 256GB pool of memory that was both storage and RAM.

 

Blurring the lines between storage and RAM is an exciting prospect - I shall be watching this one with great interest.

 

Well that's funny. After ordering my (first) SSD, last week in the pub I was having an unusually constructive discussion with a friend about whether "backing storage" and "memory" would merge at some point.

Next time I see him, I'll tell him I've had a word and it's sorted.

 

Wasn't ReRAM basically supposed to accomplish the same thing? What ever happened to that?


I'm a little skeptical of how this is supposed to be used. For example, let's say you open a spreadsheet that you want to edit. In today's computers, you read from the HDD/SDD and which loads the spreadsheet into memory. Any changes you make are entirely in memory, and that's the way it should be (in case you don't want to save).

With XPoint, I envision that in order to use it efficiently, you wouldn't be loading the file "into memory" because it's already there. But if that's the case, any changes you make to the file would be permanent whether you saved it or not. To avoid this, you have to emulate RAM, but that defeats using XPoint. In other words, what's the point of using XPoint as a merger of disk and RAM if it can't wholly replace them? It's slower than RAM, so the way I see it (depending your workload) you'd get better performance using XPoint for storage while using traditional RAM.

When it comes to read-only data, I think XPoint has a lot of potential. But at least in Windows, "read-only" is sometimes ambiguous.

 

I believe this is a product (rather than a scientific discovery) but it is being implemented into niche corners of the market just now. I imagine it would take a completely different architecture and operating system to make a true one stop shop for storage and ram.

 

I see it as working with a shadow copy.

 

Exactly - I envisage a copy-on-write model - when you open the file in read-write mode, the OS simultaneously opens it and creates a copy in a block of free space. Any changes are done on the copy. When you "save" the file, what you are really doing is changing the pointer to the file's location on the disk, so the shadow/working version then becomes the master version. Depending what you want to do, the old version can either be retained as an old version (Apple's Time Machine is probably the most widely known example of similar tech) or released as free space. This would indeed require serious changes to the way the OS works - OSes simply aren't designed to use an amorphous block of storage as both its "disk" and its "RAM".

If this can truly be made more cheaply and with higher density than flash, I expect its first commercial deployment will be in high speed enterprise grade SSDs with custom high bandwidth interconnects; later it will trickle down to consumer products as an alternative/replacement to SSD. Don't expect it by Christmas, though ;-)