MongoDB VS MySQL

Just insert test.

#!/usr/bin/ruby
 

require 'rubygems'
require 'benchmark'
 

require 'mongo'
require 'mysql'
 

# init benchmark cycle
def cycle
    10000.times{ |i|
      doc = {
        "text" => "i am any text and a little tail with me: #{i}",
        "count" => i,
        "coords" => {"x" => 203 + i, "y" => 102 + i}
      }
      

      yield doc
    }
end
 

# init mysql
mysql = Mysql.new('localhost', 'testuser', 'testpass', 'test')
mysql.query("DROP TABLE IF EXISTS `insert_bm`")
mysql.query("DROP TABLE IF EXISTS `insert_bm_coords`")
 

mysql.query("CREATE TABLE `insert_bm_coords`(
  `id` int unsigned not null auto_increment,
  `x` int not null,
  `y` int not null,
  PRIMARY KEY  (`id`)
)")
 

mysql.query("CREATE TABLE `insert_bm`(
  `id` int unsigned not null auto_increment,
  `text` varchar(255) not null,
  `count` int not null,
  `coords_id` int unsigned not null,
  PRIMARY KEY  (`id`)
)")
 

# init mongodb
mongo_db = Mongo::Connection.new.db("ololo_db")
mongo_db.collection("beta").drop
mongo = mongo_db.collection("beta")
 

# do benchmarking
Benchmark.bm {|x|
 

  x.report("mysql:") {
    cycle{|doc|
      mysql.query("INSERT insert_bm_coords(x,y) VALUES(#{doc["coords"]["x"]}, #{doc["coords"]["y"]})")
      mysql.query("INSERT insert_bm(text, count, coords_id) VALUES('#{doc["text"]}', #{doc["count"]}, #{mysql.insert_id()})")
    }
  }
  

  x.report("mongodb:") {
    cycle{|doc|
      mongo.insert(doc)
    }
  }
}
 

Result:

10_000:
   user     system      total        real
mysql:  0.300000   0.150000   0.450000 (  1.763819)
mongodb:  5.690000   0.680000   6.370000 (  7.201129)

1_000_000:
   user     system      total        real
mysql: 30.960000  12.950000  43.910000 (179.318003)
mongodb:569.650000  18.410000 588.060000 (678.889538)

UPDATE: after installing C extension (`gem install mongo_ext`).

10_000:
   user     system      total        real
mysql:  0.280000   0.110000   0.390000 (  1.679100)
mongodb:  3.110000   0.270000   3.380000 (  4.089022)

1_000_000:
   user     system      total        real
mysql: 32.400000  13.030000  45.430000 (179.684186)
mongodb:326.150000  17.000000 343.150000 (423.631974)

I'm confused. Can anybody explain it?

Что-то тут не так, учитывая заявления о скорости MongoDB.
Кто-то может подтвердить или опровергнуть?

UPDATE: here is explanation: http://blog.knopkodav.ru/2009/11/mongo-mysql-ruby-and-php.html