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DRAM Almost as Fast as SRAM

Posted by CmdrTaco on from the rammit-rammit-rammit dept.

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."

9 of 115 comments (clear)

  1. What's the point? by ArcherB · · Score: 2, Insightful

    With all these improvements in processor and RAM speed, when can I expect a faster HDD? A solid state drive would be nice.

    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.

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    1. Re:What's the point? by Waffle+Iron · · Score: 4, Insightful

      Why not concentrate on the bottlenecks rather than what is already one of the fastest components in any system.

      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.

    2. Re:What's the point? by another_fanboy · · Score: 3, Insightful

      Why not concentrate on the bottlenecks
      In comparison to the processor, is RAM not a bottleneck? An improvement in an area that has less need is still an improvement.

    3. Re:What's the point? by Anonymous Coward · · Score: 2, Insightful

      when can I expect a faster HDD? [...] Why not concentrate on the bottlenecks
      Ah, the eternal "why not cure cancer instead?". HDDs aren't the bottleneck for MANY applications, so this DRAM news matters greatly. DRAM engineers don't have the skills to improve HDDs, so you can't just have them work on your pet peeve.
    4. Re:What's the point? by Lazerf4rt · · Score: 2, Insightful

      Why not concentrate on the bottlenecks rather than what is already one of the fastest components in any system?

      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.

    5. Re:What's the point? by joto · · Score: 4, Insightful

      For random I/O, they are obscenely fast for the price...about twice the speed of two striped Raptors with a good controller.

      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?

  2. To those wondering by kestasjk · · Score: 4, Insightful

    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.

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    // MD_Update(&m,buf,j);
  3. Yes, trust IBM. by mmell · · Score: 5, Insightful
    Because everybody knows that companies should invest millions of dollars to develop technologies which should then be given away for free. That's the only workable business model, right?

    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.

  4. Re:almost as fast? by warrior · · Score: 2, Insightful

    If you've plenty of memory on-die the bus becomes irrelevant ;) That's how Intel is keeping up with AMD - big cache band-aid on the slow FSB so they can compete with HT.

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