Benchmark between Array#sort and Array#sort_by.

sorting_benchmark.rb

require 'benchmark'

@ids = (1..1000).to_a.shuffle
@records = []

1000.times do |x|
  @records << { :id => (x + 1) }
end

Benchmark.bm do |x|
  x.report { @records.sort_by { |r| @ids.index(r[:id]) } }
  x.report { @records.sort { |x, y| @ids.index(x[:id]) <=> @ids.index(y[:id]) } }
end

    user     system      total        real
0.030000   0.000000   0.030000 (  0.024707)
0.440000   0.000000   0.440000 (  0.438650)