Fluentd:PackedForward format

irb.log

irb(main):018:0> c = TCPSocket.new('127.0.0.1', 24224)
=> #<TCPSocket:fd 12>
irb(main):020:0> c.write(MessagePack.pack(['foo.bar', Time.now.to_i, {:name => 'hoge', :age => 11}]))
=> 30
irb(main):021:0> c.write(MessagePack.pack(['foo.bar', Time.now.to_i, {:name => 'hoge', :age => 11}]))
=> 30
irb(main):022:0> c.write(MessagePack.pack(['foo.bar', Time.now.to_i, {:name => 'hoge', :age => 11}]))
=> 30

msgpack.format

[
a7(fixstr:7) : foo.bar
,
db(str:66)   :
  92(fixarray:2) :
    ce(uint32)   : 0x55f80b97 => 2015-09-15 21:14:15 +0900
    82(fixmap:2) :
      a4(fixstr:4)  : name
      a4(fixstr:4)  : hoge
      a3(fixstr:3)  : age
      0b(posfixint) : 11

  92(fixarray:2) :
    ce(uint32)   : 0x55f80b98 => 2015-09-15 21:14:16 +0900
    82(fixmap:2) :
      a4(fixstr:4)  : name
      a4(fixstr:4)  : hoge
      a3(fixstr:3)  : age
      0b(posfixint) : 11

      :
]

PackedForward_message_from_irb.log

irb(main):027:0> c = TCPSocket.new('127.0.0.1', 24225)                                                                                                                            => #<TCPSocket:fd 15>
irb(main):028:0> c.write(MessagePack.pack(['foo.bar', MessagePack.pack([Time.now.to_i, {:name => 'aaa', :age => 12}]) + MessagePack.pack([Time.now.to_i, {:name => 'bbb', :age => 34}])]))
=> 54

>>>

2015-09-16 00:16:28 +0900 foo.bar: {"name":"aaa","age":12}
2015-09-16 00:16:28 +0900 foo.bar: {"name":"bbb","age":34}

tcpdump.log

21:15:11.995188 IP 127.0.0.1.57833 > 127.0.0.1.24225: Flags [FP.], seq 2:81, ack 1, win 12759, options [nop,nop,TS val 814009647 ecr 814009647], length 79
        0x0000:  4500 0083 8b10 4000 4006 0000 7f00 0001  E.....@.@.......
        0x0010:  7f00 0001 e1e9 5ea1 4780 d8b5 52f0 221c  ......^.G...R.".
        0x0020:  8019 31d7 fe77 0000 0101 080a 3084 cd2f  ..1..w......0../
        0x0030:  3084 cd2f a766 6f6f 2e62 6172 db00 0000  0../.foo.bar....
        0x0040:  4292 ce55 f80b 9782 a46e 616d 65a4 686f  B..U.....name.ho
        0x0050:  6765 a361 6765 0b92 ce55 f80b 9882 a46e  ge.age...U.....n
        0x0060:  616d 65a4 686f 6765 a361 6765 0b92 ce55  ame.hoge.age...U
        0x0070:  f80b 9982 a46e 616d 65a4 686f 6765 a361  .....name.hoge.a
        0x0080:  6765 0b                                  ge.