Intro to System Design（原声文稿）

This video is sponsored by Sevalla, more on them later.

process massive amounts of data and stay reliable no matter what.

to spin up an XJS project and then vibe code yet another to-do app.

Everything starts with knowing how the web itself works.

browser knows where to find the server it needs to reach.

information can't be read or changed by anyone intercepting your traffic.

requests and receiving responses from a server.

need in a single request, reducing over and under fetching.

data faster and more efficiently by using a binary format.

of past requests, which makes them easier to scale.

about each client, which can make certain features easier but adds complexity.

handles the response later when it arrives.

across servers so no single server is overwhelmed.

connections or weighted distribution depending on the situation.

and can act as security filters or content accelerators.

requests, while reverse proxies sit in front of servers.

around the world so users get faster access. API gateways handle requests for microservices.

client can send, and route requests to the right service.

HTTP requests and serve webpages or API responses.

Databases store the data these systems depend on.

SQL databases use structured schemas and are best when you need clear relationships are flexible and can store unstructured or semi-structured need to handle many different data types or large Indexing creates fast-lookup paths in the database to denormalization adds some duplication back in to make reads faster.

servers so the system can keep working if one server goes down.

across different machines so systems can store and process more information.

Partitioning divides data by criteria like time or region to spread load.

consistency, availability and partition tolerance at the same time.

latency and consistency tradeoffs even when there's no network failure.

operations so they all succeed or fail together.

interact to avoid problems like dirty reads or lost updates.

relates and is stored so it can grow without major changes.

it can be retrieved faster, reducing database load and latency for users.

Tools like Radies and Memcached provide in-memory storage for cache data.

Cache strategies define how data gets replaced when space runs out.

LRU removes the list recently used items, LFU removes the list frequently used. TTL sets an expiration time on cache data.

right behind caching delays database updates to improve speed.

outdated cache entries so users get fresh data.

services to communicate without waiting for each other.

temporarily store messages so they can be processed later.

trigger actions in other parts of the system.

service publishing messages and other services subscribing to receive them.

scalable because work can be spread out and processed asynchronously.

system communication between microservices needs to be reliable.

Service discovery lets services find each other automatically.

requests clients can send to prevent overwhelming services.

and temporarily stop sending requests to avoid making failures worse.

Retry logic gives systems a way to try failed operations again.

unintended effects like charging a customer twice.

keep systems fast and able to handle more users.

scaling upgrades the resources of existing machines.

CDNs and edge caching improve performance by bringing data closer to users.

Reader replicas let databases handle more read operations by duplicating data across consistency and availability is important because stricter consistency issues. Security measures keep systems and user data safe.

authorization checks what they are allowed to tools to handle these tasks with HTTPS and TLS encrypting intercepted. Encryption can also protect data stored in databases or files.

limiting help systems stay online even when attacked.

High availability and fault tolerance keep systems running when failures happen.

provides protection if one location has an outage.

automatically when a server or region fails.

ensure systems agree on which server should make decisions.

give visibility into system problems so teams can respond quickly.

designing complete systems brings everything together.

needs knowledge of storage, caching and scaling.

A rate limiter service needs to understand caching and time-based counters.

require handling large files, metadata and user permissions.

Notification systems need messaging, retries and delivery guarantees. messages.

different ways, requiring careful choices to balance speed, consistency, reliability and cost.

provide fast secure experiences to millions of users around the world.

this is when today's sponsor comes into play.

databases or static sites, offering cloud-native performance and deploy templates to accelerate your development process.

integration, your static content is globally optimized for speed.

credit, no hidden fees and predictable payments.