Assuming you have a 1GB file. According to Colossus paper, that gets split into 1MB parts, so 1000. And they probably use erasure-coding for replication. How does it work ? Do they EC each 1000 part separately, or ?
According to these slides, each stripe is a separate replication group. Although the figure depicts replicated rather than erasure coded files, I think it's safe to imagine that the idea holds for both.