Primes.go

Introduction

A quick test implementing the Sieve of Eratostenes in Go.

It searches for prime numbers up to the specified limit, optionally saving them to file.

It is one of many small programs I wrote to get a feel for #golang. If you're interested in generating prime numbers, you should probably look into primegen or some other, more suitable alternative.

Compiling

$ go build primes.go

Usage

primes [-l limit] [-s]

• -l limit (default 100000) Upper limit for prime searching
• -s (default false) Save the prime numbers to primes.txt

Running tests

$ go test

Speed

These are some non-accurate benchmarks I ran on my machine.

Specs

• AMD Phenom II X6 1055T @3.4GHz
• 8GB of cheap Kingston DDR3 @486MHz
• Windows 8 RTM 64-bit

Results

Ram usage and CPU time for finding primes up to:

       1'000'000    <1MB 2ms
      10'000'000    <1MB 26ms
     100'000'000   7.4MB 397ms
   1'000'000'000  61.2MB 8.72s
  10'000'000'000 599.8MB 1m49s

License

Copyright 2012 Martino di Filippo

Licensed under the MIT License