Github user hanm commented on a diff in the pull request:
https://github.com/apache/zookeeper/pull/605#discussion_r219628119
--- Diff:
src/java/test/org/apache/zookeeper/server/quorum/FuzzySnapshotRelatedTest.java
---
@@ -162,6 +167,98 @@ public void process(String path) {
new String(zk[followerA].getData(node2, null, null)));
}
+ /**
+ * It's possibel during SNAP sync, the parent is serialized before the
+ * child get deleted during sending the snapshot over.
+ *
+ * In which case, we need to make sure the pzxid get correctly updated
+ * when applying the txns received.
+ */
+ @Test
+ public void testPZxidUpdatedDuringSnapSyncing() throws Exception {
+ LOG.info("Enable force snapshot sync");
+ System.setProperty(LearnerHandler.FORCE_SNAP_SYNC, "true");
+
+ final String parent = "/testPZxidUpdatedWhenDeletingNonExistNode";
+ final String child = parent + "/child";
+ createEmptyNode(zk[leaderId], parent);
+ createEmptyNode(zk[leaderId], child);
+
+ LOG.info("shutdown follower {}", followerA);
+ mt[followerA].shutdown();
+ QuorumPeerMainTest.waitForOne(zk[followerA], States.CONNECTING);
+
+ LOG.info("Set up ZKDatabase to catch the node serializing in
DataTree");
+ addSerializeListener(leaderId, parent, child);
+
+ LOG.info("Restart follower A to trigger a SNAP sync with leader");
+ mt[followerA].start();
+ QuorumPeerMainTest.waitForOne(zk[followerA], States.CONNECTED);
+
+ LOG.info("Check and make sure the pzxid of the parent is the same
" +
+ "on leader and follower A");
+ compareStat(parent, leaderId, followerA);
+ }
+
+ /**
+ * It's possible during taking fuzzy snapshot, the parent is serialized
+ * before the child get deleted in the fuzzy range.
+ *
+ * In which case, we need to make sure the pzxid get correctly updated
+ * when replaying the txns.
+ */
+ @Test
+ public void testPZxidUpdatedWhenLoadingSnapshot() throws Exception {
+
+ final String parent = "/testPZxidUpdatedDuringTakingSnapshot";
+ final String child = parent + "/child";
+ createEmptyNode(zk[followerA], parent);
+ createEmptyNode(zk[followerA], child);
+
+ LOG.info("Set up ZKDatabase to catch the node serializing in
DataTree");
+ addSerializeListener(followerA, parent, child);
+
+ LOG.info("Take snapshot on follower A");
+ ZooKeeperServer zkServer =
mt[followerA].main.quorumPeer.getActiveServer();
+ zkServer.takeSnapshot(true);
+
+ LOG.info("Restarting follower A to load snapshot");
+ mt[followerA].shutdown();
+ mt[followerA].start();
+ QuorumPeerMainTest.waitForOne(zk[followerA], States.CONNECTED);
+
+ LOG.info("Check and make sure the pzxid of the parent is the same
" +
+ "on leader and follower A");
+ compareStat(parent, leaderId, followerA);
+ }
+
+ private void addSerializeListener(int sid, String parent, String
child) {
+ final ZooKeeper zkClient = zk[followerA];
+ CustomDataTree dt =
+ (CustomDataTree)
mt[sid].main.quorumPeer.getZkDb().getDataTree();
+ dt.addListener(parent, new NodeSerializeListener() {
+ @Override
+ public void nodeSerialized(String path) {
+ try {
+ zkClient.delete(child, -1);
+ LOG.info("Deleted the child node after the parent is
serialized");
+ } catch (Exception e) {
+ LOG.error("Error when deleting node {}", e);
+ }
+ }
+ });
+ }
+
+ private void compareStat(String path, int sid, int compareWithSid)
throws Exception{
+ Stat stat1 = new Stat();
+ zk[sid].getData(path, null, stat1);
+
+ Stat stat2 = new Stat();
+ zk[compareWithSid].getData(path, null, stat2);
--- End diff --
@lvfangmin we should add a try catch with retry here around
`ConnectionLossException`. I noticed this when checking the flaky test
dashboard. See one failure
[example](https://builds.apache.org/job/ZooKeeper-trunk/198/testReport/junit/org.apache.zookeeper.server.quorum/FuzzySnapshotRelatedTest/testPZxidUpdatedWhenLoadingSnapshot/)
---
