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ARMv8

101 bytes added, 00:15, 23 February 2016
big.LITTLE
Typical pairings are:
* Cortex-A17 and Cortex-A7
* (Cortex-A57 A72 or Cortex-A72A57) and (Cortex-A35 or Cortex-A53)
The advantage to big.LITTLE lies in the ability to turn off cores that are not needed. Thus, when a device such as a cellphone is performing background tasks (screen off), one little core may be used; when the device is performing basic tasks, a couple of little cores or one big core may be used; and when very demanding tasks are performed, several big cores (or all of the cores) may be turned on.
Balancing power vs. performance can be very difficult - for example, will it require less energy to keep a little core on constantly to perform a background task, or run a big core for a fraction of a second every few seconds and sleep all of the cores the rest of the time?Issues such as core affinity and cache coherency also play into balancing decisions.
Wikipedia has a [http://en.wikipedia.org/wiki/ARM_big.LITTLE page on big.LITTLE] that includes a list of known implementations.