hfutatzhanghb commented on code in PR #5597:
URL: https://github.com/apache/hadoop/pull/5597#discussion_r1205453041
##########
hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataNode.java:
##########
@@ -2630,6 +2632,31 @@ public int getActiveTransferThreadCount() {
@Override // DataNodeMXBean
public Map<String, Map<String, Long>> getDatanodeNetworkCounts() {
+ int maxDisplay =
getConf().getInt(DFSConfigKeys.DFS_DATANODE_NETWORKERRORS_DISPLAY_TOPCOUNT,
+ DFSConfigKeys.DFS_DATANODE_NETWORKERRORS_DISPLAY_TOPCOUNT_DEFAULT);
+ if (maxDisplay >= 0) {
+ ConcurrentMap<String, Map<String, Long>> map =
datanodeNetworkCounts.asMap();
+ Set<Map.Entry<String, Map<String, Long>>> entries = map.entrySet();
+ List<Map.Entry<String, Map<String, Long>>> list = new
ArrayList<>(entries);
+ Collections.sort(list, new Comparator<Entry<String, Map<String,
Long>>>() {
+ @Override
+ public int compare(Map.Entry<String, Map<String, Long>> o1,
+ Map.Entry<String, Map<String, Long>> o2) {
+ Map<String, Long> value1Map = o1.getValue();
+ Map<String, Long> value2Map = o2.getValue();
+ long compared = value2Map.getOrDefault(DataNode.NETWORK_ERRORS, 0L) -
+ value1Map.getOrDefault(DataNode.NETWORK_ERRORS, 0L);
+ return (int)compared;
+ }
+ });
+ Map<String, Map<String, Long>> resultMap = new ConcurrentHashMap<>();
+ maxDisplay = list.size() > maxDisplay ? maxDisplay : list.size();
+ for (int i = 0; i < maxDisplay; i++) {
+ resultMap.put(list.get(i).getKey(), list.get(i).getValue());
+ }
+ list.clear();
Review Comment:
Sir, it's better to clear the list here to prevent memory leak.
--
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.
To unsubscribe, e-mail: [email protected]
For queries about this service, please contact Infrastructure at:
[email protected]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
