Deduplicate Cassandra service nodes (#6207)

Deduplicate Cassandra service nodes
palantir · Aug 31, 2022 · 28e882b · 28e882b
1 parent 997830e
commit 28e882b
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Showing 2 changed files with 12 additions and 4 deletions.
diff --git a/...assandra/src/main/java/com/palantir/atlasdb/keyvalue/cassandra/pool/CassandraService.java b/...assandra/src/main/java/com/palantir/atlasdb/keyvalue/cassandra/pool/CassandraService.java
@@ -55,6 +55,8 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -132,8 +134,9 @@ public static CassandraService createInitialized(
     public void close() {}
 
     public ImmutableSet<CassandraServer> refreshTokenRangesAndGetServers() {
-        ImmutableSet.Builder<CassandraServer> servers = ImmutableSet.builder();
-        ImmutableMap.Builder<CassandraServer, String> hostToDatacentersThisRefresh = ImmutableMap.builder();
+        // explicitly not using immutable builders to deduplicate nodes
+        Set<CassandraServer> servers = new HashSet<>();
+        Map<CassandraServer, String> hostToDatacentersThisRefresh = new HashMap<>();
 
         try {
             ImmutableRangeMap.Builder<LightweightOppToken, ImmutableSet<CassandraServer>> newTokenRing =
@@ -179,9 +182,9 @@ public ImmutableSet<CassandraServer> refreshTokenRangesAndGetServers() {
                 }
             }
             tokenMap = tokensInterner.intern(newTokenRing.build());
-            hostToDatacenter = hostToDatacentersThisRefresh.build();
+            hostToDatacenter = ImmutableMap.copyOf(hostToDatacentersThisRefresh);
             logHostToDatacenterMapping(hostToDatacenter);
-            return servers.build();
+            return ImmutableSet.copyOf(servers);
         } catch (Exception e) {
             log.info(
                     "Couldn't grab new token ranges for token aware cassandra mapping. We will retry in {} seconds.",

diff --git a/changelog/@unreleased/pr-6207.v2.yml b/changelog/@unreleased/pr-6207.v2.yml
@@ -0,0 +1,5 @@
+type: fix
+fix:
+  description: Deduplicate Cassandra service nodes
+  links:
+  - https://github.com/palantir/atlasdb/pull/6207