Cloud Computing I - Week01 - 1 - Basic Fundamentals

Orientation Towards Cloud Computing Concepts: Some Basic Computer Science Fundamentals

I. Basic DS

1. Queue
   • head, tail, dequeue
2. Stack
   • Push, Pop, Top

II. Process : A Program in Action

• basically a program in action
• a process P1 is given as

graph LR
A[main()] -- calls --> B[int f1()] --> C[int f2()]

• a snapshot of a process contain
  • code, program counter, current status of stack/heap & registers and few other elements

III. Computer Architecture

CPU

Registers

Cache

Memory

Disk

• Accessing registers > cache >> Memory >> disk
• Prog gets compiled to low level machine instructions.
• CPU loads inst. in batches into memory
• on execution CPU loads data into memory

IV. Big O() Notation

• describes the upper bound on behaviour on algorithms, as some vars are scaled to infinity
• "Worst case" perfomance
• rules:
  • 1. Different steps get added
       • for e.g. O(a) and O(b) are within same function. Then, for the function BigO = O(a+b)
  • 1. Drop the Constants
       • e.g. O(N) and O(N) are within same function. Then, for the function BigO = O(N) and not O(2N)
  • 1. Differene i/p => Different Vars
       • e.g. in O(N) doesn't mean the length of the array. What you want to describe is instead O(a*b) in case array a and array b are used
  • 1. Drop non-dominate terms
       • e.g. a function has O(N) and O(N^2), so here N^2 dominates, so, N ones is dropped

V. Basic Probability

• set, subset, event,

Vi. DNS

• name resolutions, IP address, CDN(content distribution network)

VII. Graphs

• network graphs,