TemperatureAware Design温度感知的设计.ppt

Training course design
TemperatureAware Design温度感知的设计
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The Problem
Power & Thermal densities are increasing
CurreProblem: Temperature adversely affects power, performance & reliability
Solution: “Temperature-Aware” Design
Temperature Aware Design
Thermal Modeling
Estimate Operating Temperature
Simple : Allow architects to easily reason about thermal effects
Detailed : Model runtime temperature at Functional-Unit granularity
Computationally Efficient
Flexible : Easily extend to novel architectures
Dynamic Thermal Management
Use runtime behavior and thermal status to adjust/distribute workload among Functional-Units
Talk Outline
Thermal Modeling
Model Description
Validation & Case Studies
Dynamic Thermal Management
Results
Conclusions
References
Kevin Skadron et. al, “Temperature-Aware Microarchitecture”
Wei Huang et. al, Compact Thermal Modeling for Temperature-Aware Design”
Thermal Modeling
Thermal model interacts with Power, Performance, Reliability models
Design convergence requires several iterations
Heat Flow vs. Electrical Phenomenon
Both can be described by the same differential equations
Heat Flow = Electrical Current
Temperature = Voltage
Capacitance = Heat Absorption Capacity
Describe design as a Thermal RC circuit
Node = Functional Block
Solve RC equations to obtain Node Temperature
Compact Thermal Model
Equivalent Model
Equivalent Model (Cont.)
Compact Model vs. HotSpot
Arbitrary granularity grid
Thermal interface material
Spreader, Interface under the die are divided into chip granularity
Primary Heat Flow Path
Rvertical = t / (k * A)
C = Alpha * cp * ρ * A
Alpha : To account for lumped capacitor model
Cp : specific heat
ρ : material density
Equivalent Model (Secondary Path)
Interconnect Thermal Model
Self-heating power & wire length prediction
Pself = I2R
R = ρm * L / Am
Equivalent Model (Secondary Path, Cont.)
Equivalent Thermal Resistance
Model Validation & Evaluation (Primary)