Example #1
0
// Blueflood will use the finest-grained resolution which doesn't exceed the slot limit.
// Thus, if you request too many points, it will automatically reduce the resolution.
func (b *Blueflood) ChooseResolution(requested api.Timerange, smallestResolution time.Duration) time.Duration {
	// In some cases, coarser-resolution data may have a shorter TTL.
	// To accomodate these cases, it must be verified that the requested timerange will
	// actually be present for the chosen resolution.
	// TODO: figure out how to make this work with moving averages and timeshifts

	requiredAge := b.timeSource().Sub(requested.StartTime())

	for _, resolution := range Resolutions {
		survivesFor := b.config.oldestViableDataForResolution(resolution)
		if survivesFor < requiredAge {
			// The data probably won't be around for the earliest part of the timerange,
			// so don't use this resolution
			continue
		}
		if resolution.duration < requested.Resolution() {
			// Skip this timerange, it is finer than the one requested.
			continue
		}
		// Check that the timerange is large enough
		if resolution.duration >= smallestResolution {
			return resolution.duration
		}
	}
	// Leave it alone, since a better one can't be found
	return requested.Resolution()
}
Example #2
0
func addMetricPoint(metricPoint metricPoint, field func(metricPoint) float64, timerange api.Timerange, buckets [][]float64) bool {
	value := field(metricPoint)
	// The index to assign within the array is computed using the timestamp.
	// It floors to the nearest index.
	index := (metricPoint.Timestamp - timerange.Start()) / timerange.Resolution()
	if index < 0 || index >= int64(timerange.Slots()) {
		return false
	}
	buckets[index] = append(buckets[index], value)
	return true
}
Example #3
0
func (f FakeTimeseriesStorageAPI) ChooseResolution(requested api.Timerange, smallestResolution time.Duration) time.Duration {
	return requested.Resolution()
}