CHIPMAKER Intel has claimed that system-on-chip (SoC) vendors have not done enough to optimise Android for multi-core processors.
Intel's single-core Medfield Atom processor enters the market at time when almost all of the big hitting ARM vendors are focusing efforts on dual-core and quad-core processors. However Intel said that chip firms should do more to optimise Android for multi-core processors as it does not effectively make use of multiple cores.
Although Intel's Medfield Atom processor does have pseudo multi-threading capability thanks to the firm's Hyperthreading technology, Intel still needs to defend Medfield against the obvious question of how it can compete with quad-core processors from ARM chip designers Nvidia, Qualcomm and Samsung. According to Mike Bell, GM of Intel's Mobile and Communications Group, the firm's defence is that Android's thread scheduler simply isn't ready for multi-core processors.
Bell said, "If you are in a non-power constrained case, I think multiple cores make a lot of sense because you can run the cores full out, you can actually heavily load them and/or if the operating system has a good thread scheduler. A lot of stuff we are dealing with, thread scheduling and thread affinity, isn't there yet and on top of that, largely when the operating system goes to do a single task, a lot of other stuff stops. So as we move to multiple cores, we're actually putting a lot of investment into software to fix the scheduler and fix the threading so if we do multi-core products it actually takes advantage of it."
Bell also claimed that Intel's internal testing had shown multi-core implementations running slower than single core, however he did not finger any particular chip. "If you take a look a lot of handsets on the market, when you turn on the second core or having the second core there [on die], the [current] leakage is high enough and their power threshold is low enough because of the size of the case that it isn't entirely clear you get much of a benefit to turning the second core on. We ran our own numbers and [in] some of the use cases we've seen, having a second core is actually a detriment, because of the way some of the people have not implemented their thread scheduling."
Later Bell said that for some chip vendors he isn't certain what advantage they get from sticking multiple cores on a die. "I've taken a look at the multiple core implementations in the market, and frankly, in a thermal and/or power constrained environment - what has been implemented - it isn't obvious to me you really get the advantage for the size and the cost of what's going into that part," said Bell.
Finally Bell claimed that Android doesn't make use of multi-core processors, something he thought other chip firms should work on sorting out alongside Intel. "The way it's implemented right now, Android does not make as effective use of multiple cores as it could, and I think - frankly - some of this work could be done by the vendors who create the SoCs, but they just haven't bothered to do it."
Bell ended with a parting shot at other chip vendors, saying that their lack of work to improve Android's multi-threading support is what's holding performance back. "Right now the lack of software effort by some of the folks who have done their hardware implementation is a bigger disadvantage than anything else," said Bell.
Bell wouldn't give a date, or even a year when Intel will bring out multi-core Atom processors, but given that he said Intel is working on Android's thread scheduling and handling, it is safe to say that there will be a multi-core Atom chip sooner rather than later. µ