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Alluxio · Dec 7, 2023 · 83c847b · 83c847b
1 parent 38cf63b
commit 83c847b
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/dora/core/common/src/main/java/alluxio/membership/EtcdMembershipManager.java b/dora/core/common/src/main/java/alluxio/membership/EtcdMembershipManager.java
@@ -112,6 +112,8 @@ public void join(WorkerInfo workerInfo) throws IOException {
       ByteSequence keyToPut = ByteSequence.from(pathOnRing, StandardCharsets.UTF_8);
       ByteSequence valToPut = ByteSequence.from(serializedEntity);
       CompletableFuture<TxnResponse> txnResponseFut = txn
+          // version of the key indicates number of modification, 0 means
+          // this key does not exist
           .If(new Cmp(keyToPut, Cmp.Op.EQUAL, CmpTarget.version(0L)))
           .Then(Op.put(keyToPut, valToPut, PutOption.newBuilder().build()))
           .Else(isK8s ? Op.put(keyToPut, valToPut, PutOption.newBuilder().build()) :