check_circle The Short Answer: Go Stateless

Should cloud services be Stateful or Stateless?

General Rule: Build Stateless services for logic and compute. Offload state to external Stateful stores (Databases/Redis). This maximizes scalability and resilience.

Launch Simulator
Help Me Choose
Cloud Architecture Abstract

Interactive Demo

The "Chaos Monkey" Test

See why stateless architectures are preferred for cloud reliability. Send requests, store data, and then destroy a server to see what happens.

State is stored in a shared external database.
person
User
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alt_route
Load Balancer
dns
Server A
dns
Server B
dns
Server C
database
Shared DB / Redis
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> Simulator initialized. Mode: Stateless.
>> Simulation Ready. Select a mode and send a request.

* Try this: In Stateful mode, send requests until "Session Data" appears on a server. Then kill that specific server. In Stateless mode, kill any server at any time.

Deep Dive

Comparing Approaches

public

cloud_off Stateless

The server treats every request as a new transaction. It keeps no memory of previous interactions.

  • add_circle Infinite Scaling: Just add more servers. Any server can answer any request.
  • add_circle Resilience: If a server crashes, no user data is lost. The load balancer just retries elsewhere.
  • remove_circle Overhead: Must fetch data from DB/Redis for every request, adding slight latency.

Best For:

REST APIs Microservices Web Apps Serverless
save

memory Stateful

The server remembers the client's context (session) locally in memory between requests.

  • add_circle Low Latency: Data is right there in RAM. No database round-trip needed.
  • remove_circle Hard to Scale: Need "Sticky Sessions" (user must always hit the same server).
  • remove_circle Fragile: If the server dies, the session state is gone (unless complex replication is used).

Best For:

Real-time Gaming WebSockets Collaborative Editors FTP/Telnet

Decision Wizard: Which should you choose?

1. Does your application logic require extremely low latency (sub-millisecond) access to session context (e.g., high-frequency trading, FPS game server)?

Interactive Architecture Guide • Built for Educational Purposes