Difference between revisions of "DVFS"

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(Switching Overhead)
(Switching Overhead)
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[http://en.wikipedia.org/wiki/DVFS DVFS, Wikipedia]
 
[http://en.wikipedia.org/wiki/DVFS DVFS, Wikipedia]
 
An article that need to be written.
 
An article that need to be written.
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=== Video Decoding ===
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*Lee, B., Nurvitadhi, E., Dixit, R., Yu, C., and Kim, M. 2005. [http://web.engr.oregonstate.edu/~benl/Publications/Journals/JSA_DVS05.pdf Dynamic voltage scaling techniques for power efficient video decoding]. J. Syst. Archit. 51, 10-11 (Oct. 2005), 633-652.
  
 
=== Switching Overhead ===
 
=== Switching Overhead ===

Revision as of 23:17, 1 September 2010

DVFS, Wikipedia An article that need to be written.

Video Decoding

Switching Overhead

-Xeon C-state transition times
-P-state frequency example, (10 133MHz steps from 1.2GHz to 2.53Ghz)
-"On dual-core Athlon X2 and Phenom I, it was for example impossible to use DVFS and get decent HD-video decoding. There are three important performance problems with dynamic power management:
Transitioning from one P-state to another takes a while, especially if you scale up. Active cores will probe idle or lower P-state cores quite frequently. The OS power manager has to predict whether or not the process will need more processing power soon or not. As a result the OS transitions a lot slower than the hardware."
-p. 168: "Processor core (including shared cache) is unavailable for less than 2us during the frequency transition."
Power consumption table for 5600 by C-state
-p. 167: "Processor C-State Power Specifications" table power consumption by C-state
Power consumption table for several processors at different power management C-states
-20us transition overhead for all C-states?
-Overview charts on C-State configuration details wakeup times and power consumption
-Gives wakeup times, but don't know where they came from
-example power performance by P-states

DVFS Project Resources

Concise references for DVFS project from 2003 using speedstep on an IBM Thinkpad
Good linux kernel reference
  • Topic: Addressing the power cost of switching overhead in DVFS processors.

Experimental Setup

DVFS Papers

Prediction and switching overhead

DVFS in Linux