multipart_upload.rb

require 'aws-sdk'

AWS.config(
  :access_key_id => '********',
  :secret_access_key => '*******'
)

s3 = AWS::S3.new
bucket = s3.buckets['birthday-understeer']


t0 = Time.now
upload_file = (ARGV[0])
basename = File.basename(upload_file)
obj = bucket.objects[basename]
File.open (basename) do |file|
  obj.multipart_upload do |upload|
    upload.add_part(file.read )
  end
end
t1 = Time.now

puts "#{t1 - t0} sec"