// CombineClusters combines freshly found clusters with existing clusters.
//
// Algorithm:
// Run clustering and pick out the "Interesting" clusters.
// Compare all the Interesting clusters to all the existing relevant clusters,
// where "relevant" clusters are ones whose Hash/timestamp of the step
// exists in the current tile.
// Start with an empty "list".
// For each cluster:
// For each relevant existing cluster:
// Take the top 20 keys from the existing cluster and count how many appear
// in the cluster.
// If there are no matches then this is a new cluster, add it to the "list".
// If there are matches, possibly to multiple existing clusters, find the
// existing cluster with the most matches.
// Take the cluster (old/new) with the most members, or the best fit if
// they have the same number of matches.
// Return all the updated clusters.
func CombineClusters(freshSummaries, oldSummaries []*types.ClusterSummary) []*types.ClusterSummary {
ret := []*types.ClusterSummary{}
stillFresh := []*types.ClusterSummary{}
// If two cluster summaries have the same hash and same Regression direction
// then they are the same, merge them together.
for _, fresh := range freshSummaries {
for _, old := range oldSummaries {
if fresh.Hash == old.Hash && math.Signbit(fresh.StepFit.Regression) == math.Signbit(old.StepFit.Regression) {
old.Merge(fresh)
ret = append(ret, old)
break
}
}
stillFresh = append(stillFresh, fresh)
}
// Even if a summary has a different hash it might still be the same event if
// there is an overlap in the traces each summary contains.
for _, fresh := range stillFresh {
var bestMatch *types.ClusterSummary = nil
bestMatchHits := 0
for _, old := range oldSummaries {
hits := 0
for _, key := range util.AtMost(old.Keys, 20) {
if util.In(key, fresh.Keys) {
hits += 1
}
}
if hits > bestMatchHits {
bestMatchHits = hits
bestMatch = old
}
}
if bestMatch != nil {
keysLengthEqual := len(fresh.Keys) == len(bestMatch.Keys)
regressionInSameDirection := math.Signbit(fresh.StepFit.Regression) == math.Signbit(bestMatch.StepFit.Regression)
freshHasBetterFit := math.Abs(fresh.StepFit.Regression) > math.Abs(bestMatch.StepFit.Regression)
freshHasMoreKeys := len(fresh.Keys) > len(bestMatch.Keys)
if freshHasMoreKeys || (keysLengthEqual && regressionInSameDirection && freshHasBetterFit) {
fresh.Status = bestMatch.Status
fresh.Message = bestMatch.Message
fresh.ID = bestMatch.ID
fresh.Bugs = bestMatch.Bugs
ret = append(ret, fresh)
// Find the bestMatch in oldSummaries and replace it with fresh.
for i, oldBest := range oldSummaries {
if oldBest == bestMatch {
oldSummaries[i] = fresh
break
}
}
}
} else {
ret = append(ret, fresh)
}
}
return ret
}
// CombineClusters combines freshly found clusters with existing clusters.
//
// Algorithm:
// Run clustering and pick out the "Interesting" clusters.
// Compare all the Interesting clusters to all the existing relevant clusters,
// where "relevant" clusters are ones whose Hash/timestamp of the step
// exists in the current tile.
// Start with an empty "list".
// For each cluster:
// For each relevant existing cluster:
// Take the top 20 keys from the existing cluster and count how many appear
// in the cluster.
// If there are no matches then this is a new cluster, add it to the "list".
// If there are matches, possibly to multiple existing clusters, find the
// existing cluster with the most matches.
// Take the cluster (old/new) with the most members, or the best fit if
// they have the same number of matches.
// Return all the updated clusters.
func CombineClusters(freshSummaries, oldSummaries []*types.ClusterSummary) []*types.ClusterSummary {
ret := []*types.ClusterSummary{}
stillFresh := []*types.ClusterSummary{}
// If two cluster summaries have the same hash and same Regression direction
// then they are the same, merge them together.
for _, fresh := range freshSummaries {
found := false
for _, old := range oldSummaries {
if fresh.Hash == old.Hash && math.Signbit(fresh.StepFit.Regression) == math.Signbit(old.StepFit.Regression) {
old.Merge(fresh)
glog.Infof("Updating Traces for: %d", old.ID)
old.Traces = fresh.Traces
ret = append(ret, old)
found = true
break
}
}
if !found {
stillFresh = append(stillFresh, fresh)
}
}
// Now process the remaining fresh clusters.
for _, fresh := range stillFresh {
// Even if a summary has a different hash it might still be the same event if
// there is an overlap in the traces each summary contains. Remember that hashes
// may move as backfilling occurs.
var bestMatch *types.ClusterSummary = nil
bestMatchHits := 0
for _, old := range oldSummaries {
hits := 0
for _, key := range util.AtMost(old.Keys, 20) {
if util.In(key, fresh.Keys) {
hits += 1
}
}
if hits > bestMatchHits {
bestMatchHits = hits
bestMatch = old
}
}
if bestMatch != nil { // There is at least one common trace.
regressionInSameDirection := math.Signbit(fresh.StepFit.Regression) == math.Signbit(bestMatch.StepFit.Regression)
freshHasBetterFit := math.Abs(fresh.StepFit.Regression) > math.Abs(bestMatch.StepFit.Regression)
if regressionInSameDirection && freshHasBetterFit {
fresh.Merge(bestMatch)
fresh.Status = bestMatch.Status
fresh.Message = bestMatch.Message
fresh.ID = bestMatch.ID
fresh.Bugs = bestMatch.Bugs
ret = append(ret, fresh)
// Find the bestMatch in oldSummaries and replace it with fresh.
for i, oldBest := range oldSummaries {
if oldBest == bestMatch {
oldSummaries[i] = fresh
break
}
}
} else {
ret = append(ret, bestMatch)
}
} else {
ret = append(ret, fresh)
}
}
return ret
}
