jiajunwang commented on a change in pull request #365: Fix RoutingTableProvider statePropagationLatency metric reporting bug URL: https://github.com/apache/helix/pull/365#discussion_r308549588
########## File path: helix-core/src/main/java/org/apache/helix/common/caches/CurrentStateSnapshot.java ########## @@ -32,18 +37,32 @@ public CurrentStateSnapshot(final Map<PropertyKey, CurrentState> currentStateMap if (_updatedStateKeys != null && _prevStateMap != null) { // Note if the prev state map is empty, this is the first time refresh. // So the update is not considered as "recent" change. + int driftCnt = 0; // clock drift count for comparing timestamp for (PropertyKey propertyKey : _updatedStateKeys) { CurrentState prevState = _prevStateMap.get(propertyKey); CurrentState curState = _properties.get(propertyKey); Map<String, Long> partitionUpdateEndTimes = null; for (String partition : curState.getPartitionStateMap().keySet()) { long newEndTime = curState.getEndTime(partition); - if (prevState == null || prevState.getEndTime(partition) < newEndTime) { + if (prevState == null + || prevState.getEndTime(partition) < newEndTime && prevState.getEndTime(partition) != -1) { if (partitionUpdateEndTimes == null) { partitionUpdateEndTimes = new HashMap<>(); } partitionUpdateEndTimes.put(partition, newEndTime); + } else if (prevState != null && prevState.getEndTime(partition) > newEndTime) { + // This can happen due to clock drift. + // updatedStateKeys is the path to resource in an instance config. + // Thus, the space of inner loop is Sigma{replica(i) * partition(i)}; i over all resources in the cluster + // This space can be large. In order not to print two many lines, we print first warning for the first case. Review comment: I think there are some typos in the comment, please fix : ) For example, > In order not to print two many lines ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services