Computer Architecture · Cluster
Architecture Tradeoffs
Power, area, and performance budgets.
- 01 The Power Wall: Why Frequency Scaling Stopped How dynamic power depends on voltage and frequency, why Dennard scaling ended when the supply voltage stopped falling, and what replaced clock rate as the source of throughput.
- 02 The Area Budget: Reticle Limits, Yield, and Cost per Die Why a die cannot grow past the lithography field, how defect density makes cost superlinear in area, and what a square millimetre of silicon actually buys.
- 03 Clock and Power Gating: Computing the Break-Even Point How gating removes switching power from idle units, what state retention and inrush current cost, and the idle duration at which each form of gating starts to pay.
- 04 Thermal Design Power and the Throttling It Authorises What a TDP rating specifies, why a part may exceed it briefly, how the control loop reacts to temperature and current limits, and why two parts with the same TDP perform differently.
- 05 Power Density and the Dark Silicon Constraint Why a chip can contain more transistors than its power budget can switch at once, how that forces area to be specialised, and what fraction of a die can be active at any instant.
- 06 Voltage and Frequency Domains: Why DVFS Is Not One Knob How a frequency change requires a voltage change, why level shifters and synchronisers appear at domain boundaries, and what latency an operating-point transition really costs.
- 07 Issue Width and Its Diminishing Returns Why widening an out-of-order issue window costs area and energy faster than it buys performance, and where the wakeup, select, and bypass networks set the ceiling.
- 08 Chiplets and the Cost of Leaving the Die What partitioning buys in yield and reticle headroom, and what the die-to-die interface costs in energy per bit, latency, and package complexity.
- 09 Heterogeneous Cores and the Area-Performance Frontier Why a large core and a small core can be combined to beat either alone, how area efficiency curves determine the mix, and what thread migration costs.
- 10 Specialisation as an Energy Strategy Why a fixed-function unit beats a general-purpose core on energy per operation, how Amdahl and utilisation bound the payoff, and what the built-in generality of a core is worth.