1. Instruction Set Architecture (ISA) is a “contract” between SW programmers and HW designers.

  2. Computer architecture: Cover many levels of abstractions including ISA, organization, and hardware implementation (Micro-architectures)

    Includes ISA and its microarchitectures.

  3. Moore’s law: It originally stated that the number of transistors on a microchip would double every year while the costs would be halved. In 1975, Moore revised this forecast to doubling approximately every two years.

  4. Each time the cost or performance improves by 10x, new applications emerge.

  5. More transistors → Higher performance? (Multiplier/Divider, Pipelining, Superscalar并行/VLIW多个指令打包成一条更长的指令/Out-of-Order乱序执行, Multi-cores并行, Cache hierarchy, Vector同时处理多个数据/SIMD units处理器在同一时刻对多个数据执行相同的操作)

  6. Classes of Computers:

    1. Desktop computers (PC/Workstations): deliver good performance to a single user at a low cost.

    2. Servers/Mainframes: run larger programs for multiple users simultaneously, typically accessed via a network, emphasizing dependability and security.

    3. Embedded computers (microprocessors): A computer within another system with a dedicated function or application.

    4. Supercomputers: with the highest performance and cost; FLOPS每秒浮点运算次数 → 衡量计算速度; modern supercomputers reach petaFLOPS and exaFLOPS range.

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  7. Post-PC Era: Personal Mobile Devices, Warehouse-Scale Computers (large-scale direction, providing software as a service (SaaS)软件即服务 → 用户只需要通过网络访问服务，不必在本地安装复杂的软件)

  8. Supercomputers vs. Whare-House Computers

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1.2 Eight Great Ideas in Computer Architecture

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Design for where it will be when finishes rather than design for where it starts.

ILP（指令级并行）、TLP（线程级并行）、DLP（数据级并行）、MLP（内存级并行）和RLP（请求级并行）

流水线技术将一个复杂的任务拆分为多个简单的步骤，多个步骤可以同时进行。相比于等一个产品完全生产完再开始下一个产品的生产，会快很多；希望每一个流程的时间是相对均匀的。

Prediction: