dotcloud/docker — pull request #6821 by LK4D4 (2014-07-02 19:31:14+00:00)
Title: Broadcast writer refactor

Benchmark results:
```
benchmark old ns/op new ns/op delta
BenchmarkBroadcastWriter 5932520 5468662 -7.82%

benchmark old allocs new allocs delta
BenchmarkBroadcastWriter 8712 7549 -13.35%

benchmark old bytes new bytes delta
BenchmarkBroadcastWriter 1180412 591206 -49.92%
```