Exponental Backoff

Exponential backoff vs. simple backoff simulation in Go.

Part of highload and reliability workshop (часть мастер-класса про высокие нагрузки и надежность) http://smira.highload.ru/ (in Russian).

Building

You need go 1.1+ to build this program. Go can be downloaded from http://golang.org/doc/install or installed as package for your OS.

To build:

go build -o client client.go
go build -o server server.go

You should have two programs: client and server.

Running

First, it is recommended to raise limits on number of open files, e.g.:

ulimit -n 10000

Start server:

./server

In different terminal, try starting client:

./client

This would start client with simple (fixed) delay in case of request error. Try stopping server with ^Z. Watch client discovering server being unavailable, and bring server back by running command fg. See how server "dies" under storm of connections from the client. Repeat the same with exponential backoff in client:

./client -exponential-backoff

A lot of options, timeouts, etc. could be controlled with command-line flags:

./client -h
./server -h

Have fun!