type extraStringID uint64

// stackID is an index into the stack table for a generation.
type stackID uint64

// cpuSample represents a CPU profiling sample captured by the trace.
type cpuSample struct {
	schedCtx
	time  Time
	stack stackID
}

// asEvent produces a complete Event from a cpuSample. It needs
// the evTable from the generation that created it.
//

type Reader struct {
	r           *bufio.Reader
	lastTs      Time
	gen         *generation
	spill       *spilledBatch
	spillErr    error // error from reading spill
	frontier    []*batchCursor
	cpuSamples  []cpuSample
	order       ordering
	emittedSync bool

	go121Events *oldTraceConverter
}

// NewReader creates a new trace reader.
func NewReader(r io.Reader) (*Reader, error) {
	br := bufio.NewReader(r)