Welcome to MkDocs

Project layout

HLD - Book, Jordan, Hello Interview, Any video. The point is it will be topic wise. Like any topic I got anywhere I will add it in single place.

Example - Most commonly asked and pattern. LLD - Pattern Example. Most asked end to end. Multithreading.

Java Project. Spring project Interview Guide.

Microservice Architecture.

AI ML - Core to advanced role - Backend AI Engineer.

Run the project - python -m mkdocs serve and mkdocs serve

Scan in 10 seconds

Revise in 2 minutes

Remember key points
To deploy - push the code in github and mkdocs gh-deploy.

Adding image.

Inside docs - images - SystemDesign - Image.png and the file are in say docs - SystemDesign - file.md the url will be go to the main folder then image.

The image url - ![NetworkLayer](../images/SystemDesign/NetworkLayer.png)

The tag in the base doc branch.

Making the image small - <img src="/images/SystemDesign/NetworkLayer.png" style="width:60%;">

https://suchismita-deb.github.io/blogSystemDesign/

Practice UML diagram to get teh class relationship of the system and no need to write to the code. Design Pattern and UML diagram.

System Design PDF

git config user.name
git config user.email
git config http.sslVerify false
git push origin main

External monitor works - Extend display (There Settings - Display there will be 2 screens and moving the cursor to the left or right will point to the monitor or laptop screen) - Making any app visible in monitor then open the app and then Win+Shift+Right/LeftKey.
Duplicate Screen will open all in the laptop and monitor.

distinctElementOptimized arr[] = [1, 2, 1, 3, 4, 2, 3] [3, 4, 4, 3]

int nums[] and int k. Find the distinct nums in k size window in the array.

import java.util.HashMap;
import java.util.Map;

int[] distinctElementOptimized(int nums[], int target) {
    Map<Integer, Integer> mp = new HashMap<>();

    int arr[] = new int[n-k+1];
    for(int i=0;i<k;i++){
        mp.put(nums[i],mp.getOrDefault(mp.get(nums[i]),0)+1);
    }
    int pointer=0;
    int pos=1;
    arr[0] = mp.size();
    for(int i=k;i<n;i++){
        mp.put(nums[pointer], mp.get(nums[pointer])-1);
        if(mp.get(nums[pointer])==0) {
            mp.remove(nums[pointer]);
        }
        mp.put(nums[i],mp.getOrDefault(mp.get(nums[i]),0)+1);
        arr[pos++] = mp.size();
    }
    return arr;
}

What is concurrentHashMap. What is the HashMap internal. Kafka Partition ordering. What is the equals method.

In Spring project in the properties file when set it like spring.ai.openai.api-key=${OPENAI_API_KEY} In the env edit configuration in the Modify Options add the OPENAI_API_KEY="Val" The apply and run.

System Design Mind Map

# System Design

## Key Technology Week 1 to 7

### Data Structure
- Stack and Queue
- Priority Queue
- B Tree and Trie

### Networking
- HTTP/HTTPs, TCP/IP, UDP
- DNS Resolution
- TCp 3 way handshake
- REST API and Status Code
- Latency and throughput

### OS Concepts
- Threads and Process
- CPU Scheduling and Context Switching
- IO Blocking and Async Operations
- Virtual Memory and Paging
- File System and Storage
### DB Concepts
- Sharding and Partitioning
- Replication Models
- Read/Write Replicas
- CAP Theorem and Trade-offs
- Consistency Models
  - Eventual Consistency
  - Strong Consistency

### Load Balancing and Scaling
- Vertical Scaling
- Horizontal Scaling
- L4 Load Balancer
- L7 Load Balancer
- DNS-Based Load Balancing
- Health Check and Failover
- Consistent Hashing

### Caching System
- Redis
- Memcache
- Eviction Policy
  - LRU
  - LFU
  - FIFO
- Write Strategy
  - Write-through
  - Write-back

### Event and Messaging
- Message Brokers
  - Kafka
  - RabbitMQ
- Sync and Async Communication
- Pub/Sub Models
- Delivery Guarantees and Ordering
- Dead Letter Queue and Retries

## Design Architecture
### Design Thinking
- Requirement
- Bottleneck Identification
- Data and Control Flow
- Stateless and Stateful
  - Between two requests, if we need to maintain a session, then it is stateful.
- Failure Handling
### Design Pattern
- Rate Limiting
  - Token Bucket
  - Leaky Bucket
  - Sliding Window
- Circuit Breaker and Retry Logic
- Leader Election
- Health Checks and Heartbeats
- CQRS and Event Sourcing
### Design Architecture
- Monolithic
- Microservices
- Event-Driven
- Layered Architecture
- Client-Server
- Service-Oriented
## Practice
### Practice Pattern Question.
- File Storage and Sharing
  - Drive
  - Github
  - Pinterest
  - OneDrive
  - Photos
- Social Media and Networking
  - Facebook
  - Instagram Reels
  - Twitter Feed
    - Newsfeed generation
    - Recommendation system
  - LinkedIn
  - Reddit
  - Snapchat
- Likes Count
  - Instagram Reel like and comment
- Messaging and Communication
  - WhatsApp
    - Real-time messaging
    - Group chat
    - Video streaming
  - Telegram
  - Slack
  - Zoom
  - Teams
- Search and Discovery
  - Google Search
  - Amazon Product Search
    - Indexing
    - Ranking algorithm
    - Query optimization
    - Caching
- Ride Sharing
  - Uber
  - Swiggy
  - DoorDash
  - Google Maps
    - Real-time location tracking
    - Dispatch algorithm
    - Route optimization
- Content Delivery
  - Netflix
  - Disney Hotstar
  - Spotify
  - YouTube Live
    - Video encoding
    - Live streaming latency
- Ecommerce
  - Amazon
  - eBay
  - Airbnb
- Payment System
  - PayPal
  - Cash App
- Collaboration
  - Google Docs
  - Jira
  - Notion
- Content Publishing
  - Medium
  - Quora
- Healthcare and Fitness
  - Practo
  - Fitbit
- Gaming and High Traffic
  - PUBG
  - Discord
- Ad Tech and Recommendation
  - Google Ads
  - YouTube