示例#1
0
// findTimeSeries searches the supplied engine over the supplied key range,
// identifying time series which have stored data in the range, along with the
// resolutions at which time series data is stored. A unique name/resolution
// pair will only be identified once, even if the range contains keys for that
// name/resolution pair at multiple timestamps or from multiple sources.
//
// An engine snapshot is used, rather than a client, because this function is
// intended to be called by a storage queue which can inspect the local data for
// a single range without the need for expensive network calls.
func findTimeSeries(
	snapshot engine.Reader, startKey, endKey roachpb.RKey, now hlc.Timestamp,
) ([]timeSeriesResolutionInfo, error) {
	var results []timeSeriesResolutionInfo

	iter := snapshot.NewIterator(false)
	defer iter.Close()

	// Set start boundary for the search, which is the lesser of the range start
	// key and the beginning of time series data.
	start := engine.MakeMVCCMetadataKey(startKey.AsRawKey())
	next := engine.MakeMVCCMetadataKey(keys.TimeseriesPrefix)
	if next.Less(start) {
		next = start
	}

	// Set end boundary for the search, which is the lesser of the range end key
	// and the end of time series data.
	end := engine.MakeMVCCMetadataKey(endKey.AsRawKey())
	lastTS := engine.MakeMVCCMetadataKey(keys.TimeseriesPrefix.PrefixEnd())
	if lastTS.Less(end) {
		end = lastTS
	}

	thresholds := computeThresholds(now.WallTime)

	for iter.Seek(next); iter.Valid() && iter.Less(end); iter.Seek(next) {
		foundKey := iter.Key().Key

		// Extract the name and resolution from the discovered key.
		name, _, res, tsNanos, err := DecodeDataKey(foundKey)
		if err != nil {
			return nil, err
		}
		// Skip this time series if there's nothing to prune. We check the
		// oldest (first) time series record's timestamp against the
		// pruning threshold.
		if threshold, ok := thresholds[res]; !ok || threshold > tsNanos {
			results = append(results, timeSeriesResolutionInfo{
				Name:       name,
				Resolution: res,
			})
		}

		// Set 'next' is initialized to the next possible time series key
		// which could belong to a previously undiscovered time series.
		next = engine.MakeMVCCMetadataKey(makeDataKeySeriesPrefix(name, res).PrefixEnd())
	}

	return results, nil
}
示例#2
0
// NewReplicaDataIterator creates a ReplicaDataIterator for the given replica.
func NewReplicaDataIterator(
	d *roachpb.RangeDescriptor, e engine.Reader, replicatedOnly bool,
) *ReplicaDataIterator {
	rangeFunc := makeAllKeyRanges
	if replicatedOnly {
		rangeFunc = makeReplicatedKeyRanges
	}
	ri := &ReplicaDataIterator{
		ranges:   rangeFunc(d),
		iterator: e.NewIterator(false),
	}
	ri.iterator.Seek(ri.ranges[ri.curIndex].start)
	ri.advance()
	return ri
}
示例#3
0
文件: stats.go 项目: knz/cockroach
// ComputeStatsForRange computes the stats for a given range by
// iterating over all key ranges for the given range that should
// be accounted for in its stats.
func ComputeStatsForRange(
	d *roachpb.RangeDescriptor, e engine.Reader, nowNanos int64,
) (enginepb.MVCCStats, error) {
	iter := e.NewIterator(false)
	defer iter.Close()

	ms := enginepb.MVCCStats{}
	for _, r := range makeReplicatedKeyRanges(d) {
		msDelta, err := iter.ComputeStats(r.start, r.end, nowNanos)
		if err != nil {
			return enginepb.MVCCStats{}, err
		}
		ms.Add(msDelta)
	}
	return ms, nil
}
示例#4
0
// findTimeSeries searches the supplied engine over the supplied key range,
// identifying time series which have stored data in the range, along with the
// resolutions at which time series data is stored. A unique name/resolution
// pair will only be identified once, even if the range contains keys for that
// name/resolution pair at multiple timestamps or from multiple sources.
//
// An engine snapshot is used, rather than a client, because this function is
// intended to be called by a storage queue which can inspect the local data for
// a single range without the need for expensive network calls.
func findTimeSeries(
	snapshot engine.Reader, startKey, endKey roachpb.RKey,
) ([]timeSeriesResolutionInfo, error) {
	var results []timeSeriesResolutionInfo

	iter := snapshot.NewIterator(false)
	defer iter.Close()

	// Set start boundary for the search, which is the lesser of the range start
	// key and the beginning of time series data.
	start := engine.MakeMVCCMetadataKey(startKey.AsRawKey())
	next := engine.MakeMVCCMetadataKey(keys.TimeseriesPrefix)
	if next.Less(start) {
		next = start
	}

	// Set end boundary for the search, which is the lesser of the range end key
	// and the end of time series data.
	end := engine.MakeMVCCMetadataKey(endKey.AsRawKey())
	lastTS := engine.MakeMVCCMetadataKey(keys.TimeseriesPrefix.PrefixEnd())
	if lastTS.Less(end) {
		end = lastTS
	}

	for iter.Seek(next); iter.Valid() && iter.Less(end); iter.Seek(next) {
		foundKey := iter.Key().Key

		// Extract the name and resolution from the discovered key.
		name, _, res, _, err := DecodeDataKey(foundKey)
		if err != nil {
			return nil, err
		}
		results = append(results, timeSeriesResolutionInfo{
			Name:       name,
			Resolution: res,
		})

		// Set 'next' is initialized to the next possible time series key
		// which could belong to a previously undiscovered time series.
		next = engine.MakeMVCCMetadataKey(makeDataKeySeriesPrefix(name, res).PrefixEnd())
	}

	return results, nil
}