(accumulo) branch 2.1 updated: adds trace logging of tserver set diffs to TGW (#4695)

[kturner]

This is an automated email from the ASF dual-hosted git repository.

kturner pushed a commit to branch 2.1
in repository https://gitbox.apache.org/repos/asf/accumulo.git


The following commit(s) were added to refs/heads/2.1 by this push:
     new 75b889c83e adds trace logging of tserver set diffs to TGW (#4695)
75b889c83e is described below

commit 75b889c83e26b794b3c83c0ce0fc7cacd54d5ba1
Author: Keith Turner <ktur...@apache.org>
AuthorDate: Tue Jun 25 12:59:53 2024 -0400

    adds trace logging of tserver set diffs to TGW (#4695)
    
    This logging may be useful when debugging issues with
    balancing in the manager.
---
 .../java/org/apache/accumulo/manager/TabletGroupWatcher.java | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git 
a/server/manager/src/main/java/org/apache/accumulo/manager/TabletGroupWatcher.java
 
b/server/manager/src/main/java/org/apache/accumulo/manager/TabletGroupWatcher.java
index 827f688c49..8e4eb0768e 100644
--- 
a/server/manager/src/main/java/org/apache/accumulo/manager/TabletGroupWatcher.java
+++ 
b/server/manager/src/main/java/org/apache/accumulo/manager/TabletGroupWatcher.java
@@ -109,6 +109,7 @@ import org.slf4j.event.Level;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableSortedSet;
 import com.google.common.collect.Iterators;
+import com.google.common.collect.Sets;
 
 abstract class TabletGroupWatcher extends AccumuloDaemonThread {
 
@@ -143,7 +144,16 @@ abstract class TabletGroupWatcher extends 
AccumuloDaemonThread {
    * time an assignment scan was started.
    */
   synchronized boolean isSameTserversAsLastScan(Set<TServerInstance> 
candidates) {
-    return candidates.equals(lastScanServers);
+    boolean same = candidates.equals(lastScanServers);
+    if (!same && Manager.log.isTraceEnabled()) {
+      Manager.log.trace("{} set difference candidates-lastScanServers : {}", 
store.name(),
+          Sets.difference(candidates, lastScanServers));
+      Manager.log.trace("{} set difference lastScanServers-candidates : {}", 
store.name(),
+          Sets.difference(lastScanServers, candidates));
+      Manager.log.trace("{} set intersection(lastScanServers,candidates) size 
: {}", store.name(),
+          Sets.intersection(lastScanServers, candidates).size());
+    }
+    return same;
   }
 
   /**