Slashdot Mirror
DRAM Almost as Fast as SRAM
An anonymous reader writes "IBM said it has been able to speed up the DRAM to the point where it's nearly as fast as SRAM, and that the result is a type of memory known as embedded DRAM, or eDRAM, that helps boost the performance of chips with multiple core calculating engines and is particularly suited for enabling the movement of graphics in gaming and other multimedia applications. DRAM will also continue to be used off the chip."
Firstly, system memory is not especially fast compared to the CPU, and the recent proliferation of multiple cores is making the situation worse because more CPUs are trying to bang on the same memory.
Secondly, the most straightforward way to paper over problems with high-latency devices is to put a cache in front of them. Super fast DRAM would be one way to enable bigger caches that reduce the impact of various system bottlenecks. Sure we can hope to replace all hard drives with solid state devices, but since they still cost orders of magnitude more per megabyte, it will probably be quite a while before that happens. In the mean time, better caches couldn't hurt.
To those wondering why it would be good to have DRAM as fast as SRAM: SRAM doesn't need to be "refreshed" constantly, and is faster, but takes up many more transistors and is therefore much less dense and more expensive for the same amount of memory.
However with DRAM it takes quite a bit of power just to keep data in memory (because of the constant "refreshes"), which isn't the case with SRAM. So this discovery wouldn't take SRAM out of production for applications which require its low power usage.
// MD_Update(&m,buf,j);
No, I'm not a fan of patent trolls; but this isn't patent trolling. IBM has created a new, better way to embed cache RAM on the CPU die, at a signifigant cost in both manpower and materiel. This isn't like they patented "a method to check customers out with one click" or something similarly banal. This is a real, new technology which took a great deal of time, energy and work to create. No "prior art", no "trivially obvious" - this is exactly the kind of technological advancement which patents should protect.
Yeah, but wouldn't it be better to buy a real computer with room for more RAM, so you didn't have to use a hardware device to imitate another hardware device, so that you could use software to imitate the drivers of the other hardware device, so that you could use it as the first kind of hardware device, just with lower speed and convenience? Or in other words: wouldn't it be better to just run the database in RAM?