Erlang is a concurrent, fault-tolerant, and distributed programming language created in 1986. It uses an actor model and immutable data to allow for concurrency without race conditions. Erlang is fault-tolerant as it is designed to "let programs crash" gracefully and restart without needing to restart the entire system. It can distribute processes across multiple nodes in a network to improve reliability, scalability, and performance without single points of failure. Nodes communicate using Erlang's built-in port manager and distributed protocol without needing an interface definition language.

1. Hamidreza Soleimani
Practical Look at Erlang
Concurrent, Fault Tolerant and Distributed Programming Language
Tehran Linux User Group
February 18, 2014

2. Strong Typing
Functional
Garbage Collected
Runtime System
Erlang Birthday: 1986
History &
Philosophy

3. Fault Tolerant DistributedConcurrent
History &
Philosophy

4. 1. Concurrent
Sequential
Concurrent
Parallel

5. 1. Concurrent
Hamid RezaMajid
Actor Model
Async / Sync
Immutable
No Race Condition
Reenterancy Light Process
HiHi
Fine?
Hi
Fine!
Hi
Light
Hi
Wear

6. 2. Fault Tolerant
CorrectiveDefensive
“ Let it crash! ”“ Try to survive! ”

7. 2. Fault Tolerant
In Failure
“ Doesn't Need Restart ”“ Needs Restart ”
Human
Hot Swapping Feature
Example: Apache Example: Yaws

8. 3. Distributed
Load
Balancer
N1
N 4
N 3
N 2
N1
N 4
N 3
N 2
N1
N 4
N 3
N 2 Zone 2
Zone 3
Zone 1
Reliability
Scalability
Performance
No Single
Point of
Failure

9. 3. Distributed
epmd
Node 1
Hamid
Port: 4369
Node 2
Majid
Port: 42042Port: 42043
Erlang Port Manager Daemon
Erlang Distributed Protocol
No Need to IDL

10. Question?
­ Hamidreza.s@gmail.com