benchmark

type Options struct {
	CloudURL   string // gs://bucket/[prefix]
	LocalDir   string
	Size       int64
	MaxWorkers int
	BlockSize  int64
	RandReads  int
	DryRun     bool
	OutPath    string
	Benchmarks []string    // if non-empty, only run these benchmark names
	Labels     [][2]string // extra columns appended to every CSV row: [colName, value]
}