$ go test -v -race ./...
github.com/couchbase/moss.(*collection).updateStats()
/Users/steveyen/go/src/github.com/couchbase/moss/collection.go:427 +0x313
Previous write at 0x00c4204a4000 by goroutine 26:
github.com/couchbase/moss.(*segment).Swap()
/Users/steveyen/go/src/github.com/couchbase/moss/segment.go:274 +0x176
Here...