DRAM Almost as Fast as SRAM 115
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."
What's the point? (Score:2, Insightful)
All chips wait at the same speed. Why not concentrate on the bottlenecks rather than what is already one of the fastest components in any system.
Re:What's the point? (Score:5, Insightful)
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 (Score:5, Insightful)
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.
Re:What's the point? (Score:3, Insightful)
In comparison to the processor, is RAM not a bottleneck? An improvement in an area that has less need is still an improvement.
Re:What's the point? (Score:2, Insightful)
Re:What's the point? (Score:3, Insightful)
RAM speed is one of the biggest bottlenecks on your system. It's called a cache miss. When your CPU tries to access data outside its local cache, it has to wait for that cache line to come from system RAM. Your CPU currently spends a huge fraction of its execution time doing that. If IBM can provide a significantly faster type of system RAM, they can reduce that huge fraction, which would noticeably speed up the entire system.
Cache misses are also the whole reason why hyperthreading ended up being a good idea: it minimizes the amount of time wasted during cache misses. If system RAM was always able to deliver memory without any latency, there would not have been any point to hyperthreading.
Yes, trust IBM. (Score:5, Insightful)
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.
Re:What's the point? (Score:5, Insightful)
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?
Re:almost as fast? (Score:3, Insightful)