Lecture Notes for Operating Systems

11 September 2000 - Computer Architectures

1. computer architecture

   1. the hardware and its organization

   2. os creates an extended machine

   3. architectures are your friend or not

2. CPU

   1. arithmetic-logic unit (alu)

   2. register sets - psw, base and extent registers

   3. hardwired vs. microprogrammed control

   4. instruction sets - atomic instructions, traps

   5. interrupts - address vectors, polling

   6. protection - user-kernel, levels, masking

   7. issues - protections, irregularities, concurrency

   8. os functions - process model, scheduling

3. Storage

   1. hierarchies - external storage; main storage; cache storage

   2. External storage - see below

   3. Main storage

      1. segmented vs. flat

      2. addressing - virtual; mmu

      3. page mapping - tlb;

      4. issues - protection, performance

      5. os function - vm

   4. Cache storage - cache consistency

4. Input-Output

   1. I-O Devices - part of the address space; hardwired vs. programmable

   2. Interrupts vs dma

   3. Disks

      1. disks, arms, cylinders, sectors

      2. controller hardware - offload complexity

      3. issues - high throughput; arm scheduling; error recovery

      4. os functions - buffering, error detection and handling, load balancing.

   4. Clocks

      1. hardware or software clocks

      2. count-up timers - like wall clocks

      3. count-down timers - issue alarms

      4. issues - what is being counted? resolution

      5. os functions - virtual clocks

   5. Terminals

      1. Slow, character-oriented i-o

      2. Issues - smart vs. dumb terminals.

      3. os functions - modes (input and output processing)

   6. Networks

      1. fast, block-oriented i-o

      2. exceptional amounts of processing involved

      3. issues - driver, kernel, user processing

      4. os functions - multiplexing-demultiplexing

5. Busses

   1. Connect I-O to storage; storage to cpu

   2. issue - cache coherence

   3. os functions - consistency model

6. Oddiments

   1. multi-processor systems - smp, numa

   2. embedded systems

This page last modified on 11 September 2000