output

using Ruby 1.9.3-p327-perf
$ ruby split_benchmark.rb

naive_regex
  6.320000   0.130000   6.450000 (  6.798818)
naive_squeeze
  6.770000   0.070000   6.840000 (  7.122865)
assigned_regex
  5.710000   0.060000   5.770000 (  5.869347)
assigned_squeeze
  5.420000   0.060000   5.480000 (  5.589675)

split_benchmark.rb

require 'benchmark'

STRING = 'a^a^a^a^a^a^a^^b^^b^c'
REGEX = /^+/
SEARCH = '^'
TEST_ITERATIONS = ARGV.first || 1_000_000

def test(method)
  puts method.to_s
  puts Benchmark.measure { TEST_ITERATIONS.times { send(method) } }
end

def naive_regex
  STRING.split(/^+/)
end

def naive_squeeze
  STRING.squeeze('^').split('^')
end

def assigned_regex
  STRING.split(REGEX)
end

def assigned_squeeze
  STRING.squeeze(SEARCH).split(SEARCH)
end

[:naive_regex, :naive_squeeze, :assigned_regex, :assigned_squeeze].each do |method|
  test method
end