16-11-2010, 04:09 PM
This article describes about Chameleon, which is an application-level power management approach for reducing energy consumption in mobile processors.The improvements in battery capabilities progressed at a much slower rate than that at which the processing, storage, and communication capabilities of these devices have improved as predicted by Moore’s law. New applications like the movie players and batch compilation are very much power hungry and hence power must be managed efficiently. Modern devices use a number of power management features such as dynamic voltage and frequency scaling (DVFS) capabilities in intel's some processors. This system varies the CPU speed dynamically based on
the workload and reduces energy consumption. But sometimes, it can result in slowdown from degrading of the performance. In all cases, the nonlinear relationship
between CPU working rate and power consumption is taken advantage of.
By using application-domain knowledge, as opposed to OS-level or hardware-level inferred
knowledge, Chameleon can substantially reduce CPU energy consumption.The three three key components of Chameleon are:
a)OS interface: resource usage statistics can be queried by the applications through this and their desired power settings can be conveyed back to the kernel
b)a modified CPU scheduler: This enables the per-process CPU power settings and application isolation. the current power settings for each process is maintained by the applications and these settings are sent to the processor whenever the process is scheduled for execution.
c)a speed adapter:
This part maps application-specified power settings to the nearest CPU speed. The desired CPU speed is specified by the application as a fraction of the maximum processor speed. The function of the speed adapter is then to map this fraction to the nearest supported CPU speed.
get the report pdf here:
http://mediafire?zi07f62kodjofce
the workload and reduces energy consumption. But sometimes, it can result in slowdown from degrading of the performance. In all cases, the nonlinear relationship
between CPU working rate and power consumption is taken advantage of.
By using application-domain knowledge, as opposed to OS-level or hardware-level inferred
knowledge, Chameleon can substantially reduce CPU energy consumption.The three three key components of Chameleon are:
a)OS interface: resource usage statistics can be queried by the applications through this and their desired power settings can be conveyed back to the kernel
b)a modified CPU scheduler: This enables the per-process CPU power settings and application isolation. the current power settings for each process is maintained by the applications and these settings are sent to the processor whenever the process is scheduled for execution.
c)a speed adapter:
This part maps application-specified power settings to the nearest CPU speed. The desired CPU speed is specified by the application as a fraction of the maximum processor speed. The function of the speed adapter is then to map this fraction to the nearest supported CPU speed.
get the report pdf here:
http://mediafire?zi07f62kodjofce
