Function newSampleRing

storage/buffer.go:307–326

newSampleRing creates a new sampleRing. If you do not know the preferred value type yet, use a size of 0 (in which case the provided typ doesn't matter). On the first add, a buffer of size 16 will be allocated with the preferred type being the type of the first added sample.

(delta int64, size int, typ chunkenc.ValueType)

// matter). On the first add, a buffer of size 16 will be allocated with the
// preferred type being the type of the first added sample.
func newSampleRing(delta int64, size int, typ chunkenc.ValueType) *sampleRing {
	r := &sampleRing{delta: delta}
	r.reset()
	if size <= 0 {
		// Will initialize on first add.
		return r
	}
	switch typ {
	case chunkenc.ValFloat:
		r.fBuf = make([]fSample, size)
	case chunkenc.ValHistogram:
		r.hBuf = make([]hSample, size)
	case chunkenc.ValFloatHistogram:
		r.fhBuf = make([]fhSample, size)
	default:
		// Do not initialize anything because the 1st sample will be
		// added to one of the other bufs anyway.
	}
	return r
}

func (r *sampleRing) reset() {
	r.l = 0