embedded - Power Efficient Software Coding -

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in typical handheld/portable embedded system device battery life major concern in design of h/w, s/w , features device can support. software programming perspective, 1 aware of mips, memory(data , program) optimized code. aware of h/w deep sleep mode, standby mode used clock hardware @ lower cycles or turn of clock entirel unused circutis save power, looking ideas point of view:

wherein code running , needs keep executing, given how can write code "power" efficiently consume minimum watts?

are there special programming constructs, data structures, control structures should @ achieve minimum power consumption given functionality.

are there s/w high level design considerations 1 should keep in mind @ time of code structure design, or during low level design make code power efficient(least power consuming) possible?

  • like 1800 information said, avoid polling; subscribe events , wait them happen
  • update window content when necessary - let system decide when redraw it
  • when updating window content, ensure code recreates little of invalid region possible
  • with quick code cpu goes deep sleep mode faster , there's better chance such code stays in l1 cache
  • operate on small data @ 1 time data stays in caches well
  • ensure application doesn't unnecessary action when in background
  • make software not power efficient, power aware - update graphics less when on battery, disable animations, less hard drive thrashing

and read other guidelines. ;)

recently series of posts called "optimizing software applications power", started appearing on intel software blogs. may of use x86 developers.


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