A new memory technology coming from Rice University and UCLA could slash 30 percent or even more of the energy needed today by flash memory. Not only that, but the new “phase-change memory” (PCM) is much faster than flash (the type used in USB drives).
PCM is not new to scientists – it shares the same type of ink and working principles with CDs and DVDs (heat), but it has a drawback: writing a “0” bit, for example takes less time than reversing that bit to write a “1.”
This hurdle has to be gotten rid of, because Samsung and IBM already back the PCM technology – each of them presented a working prototype this year.
“We developed an optimization framework that exploits asymmetries in PCM read/write to minimize the number of bit transitions, which in turns yields energy and endurance efficiency,” said researcher Azalia Mirhoseini, a Rice graduate student in electrical and computer engineering, who presented the research results at the IEEE/ACM Design Automation Conference (DAC) in San Francisco.
In other words, their innovation scans entire chunks of memory to be written and only applies current to those bits that are to change, leaving the others intact, thus not wasting any more time.
This approach proved to be both energy-saving and time saving. In addition to that, it increases the lifetime of the PCM memory by up to 40 percent, just because the less you use the material by this smart method, the less it wears out.
There is also a green aspect to the expanded lifetime: it takes longer for an USB stick to end up in the same place with rotten potatoes and onions: the city dump.