Midterm Flashcards
(90 cards)
Serial
Runs one program or process at a time
Are CPU cores serial or parallel
Serial
Von Neumann Architecture
CPU and Main memory connected through interconnect
What is main memory?
Collection of locations and their contents
Parts of CPU
Control Unit and ALU
Arithmetic and Logic Unit purpose (ALU)
Executes actual instructions (worker)
Control Unit Purpose
Decides which instruction within a program should be executed (boss)
Von Neumann Bottle Neck Commands
Write/Store and Fetch/Read
Process
Instance of computer program being executed
Process Control Block (PCB)
Data structure where several components of process managed by OS are stored
What is multitasking
illusion of running multiple programs at the same time
Threading
Used to divide up work into independent tasks
Caching
Placing small fast memory near the CPU and trying to keep data we will need in there as much as possible
What helps prevent Von Neumann bottle neck
Caching
Principle of locality
How cache keeps what we need, spatial or temporal
Temporal Locality
Recently accessed data is kept in the cache
Spatial Locality
Storing data that is in the proximity of recently accessed data in the cache
Van Neumann Bottle Neck
Separation of memory and CPU
Cache Direct Mapping
Each memory location will go to same place in cache
Full Associative cache mapping
data can be placed anywhere in the cache
Set Associative Cache Mapping
Each data element has a set of locations it can be placed in
Ways for cache to handle discrepencies
Write through and write back
Write through
Caches update data in memory whenever it is written to cache
Write back
cache marks the modified data as dirty and updates the main memory only when the cache line is replaced or evicted