Handle COMMIT after NEWLEADER in DIFF sync without NPE

apache · Oct 3, 2022 · 4aab1fd · 4aab1fd
1 parent 83812a9
commit 4aab1fd
Show file tree

Hide file tree

Showing 2 changed files with 28 additions and 24 deletions.
diff --git a/zookeeper-server/src/main/java/org/apache/zookeeper/server/quorum/Learner.java b/zookeeper-server/src/main/java/org/apache/zookeeper/server/quorum/Learner.java
@@ -555,6 +555,7 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  boolean syncSnapshot = false;
  readPacket(qp);
  Deque<Long> packetsCommitted = new ArrayDeque<>();
+ Deque<PacketInFlight> packetsNotLogged = new ArrayDeque<>();
  Deque<PacketInFlight> packetsNotCommitted = new ArrayDeque<>();
  synchronized (zk) {
  if (qp.getType() == Leader.DIFF) {
@@ -643,33 +644,36 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  self.setLastSeenQuorumVerifier(qv, true);
  }
 
+ packetsNotLogged.add(pif);
  packetsNotCommitted.add(pif);
  break;
  case Leader.COMMIT:
  case Leader.COMMITANDACTIVATE:
  pif = packetsNotCommitted.peekFirst();
- if (pif.hdr.getZxid() == qp.getZxid() && qp.getType() == Leader.COMMITANDACTIVATE) {
- QuorumVerifier qv = self.configFromString(new String(((SetDataTxn) pif.rec).getData(), UTF_8));
- boolean majorChange = self.processReconfig(
- qv,
- ByteBuffer.wrap(qp.getData()).getLong(), qp.getZxid(),
- true);
- if (majorChange) {
- throw new Exception("changes proposed in reconfig");
+ if (pif.hdr.getZxid() != qp.getZxid()) {
+ LOG.warn(
+ "Committing 0x{}, but next proposal is 0x{}",
+ Long.toHexString(qp.getZxid()),
+ Long.toHexString(pif.hdr.getZxid()));
+ } else {
+ if (qp.getType() == Leader.COMMITANDACTIVATE) {
+ QuorumVerifier qv = self.configFromString(new String(((SetDataTxn) pif.rec).getData(), UTF_8));
+ boolean majorChange = self.processReconfig(
+ qv,
+ ByteBuffer.wrap(qp.getData()).getLong(), qp.getZxid(),
+ true);
+ if (majorChange) {
+ throw new Exception("changes proposed in reconfig");
+ }
  }
- }
- if (!writeToTxnLog) {
- if (pif.hdr.getZxid() != qp.getZxid()) {
- LOG.warn(
- "Committing 0x{}, but next proposal is 0x{}",
- Long.toHexString(qp.getZxid()),
- Long.toHexString(pif.hdr.getZxid()));
- } else {
+ if (!writeToTxnLog) {
  zk.processTxn(pif.hdr, pif.rec);
+ packetsNotLogged.remove();
+ packetsNotCommitted.remove();
+ } else {
  packetsNotCommitted.remove();
+ packetsCommitted.add(qp.getZxid());
  }
- } else {
- packetsCommitted.add(qp.getZxid());
  }
  break;
  case Leader.INFORM:
@@ -708,7 +712,7 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  // Apply to db directly if we haven't taken the snapshot
  zk.processTxn(packet.hdr, packet.rec);
  } else {
- packetsNotCommitted.add(packet);
+ packetsNotLogged.add(packet);
  packetsCommitted.add(qp.getZxid());
  }
 
@@ -756,10 +760,10 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  zk.startupWithoutServing();
  if (zk instanceof FollowerZooKeeperServer) {
  FollowerZooKeeperServer fzk = (FollowerZooKeeperServer) zk;
- for (PacketInFlight p : packetsNotCommitted) {
+ for (PacketInFlight p : packetsNotLogged) {
  fzk.logRequest(p.hdr, p.rec, p.digest);
  }
- packetsNotCommitted.clear();
+ packetsNotLogged.clear();
  }
 
  writePacket(new QuorumPacket(Leader.ACK, newLeaderZxid, null, null), true);
@@ -782,7 +786,7 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  // We need to log the stuff that came in between the snapshot and the uptodate
  if (zk instanceof FollowerZooKeeperServer) {
  FollowerZooKeeperServer fzk = (FollowerZooKeeperServer) zk;
- for (PacketInFlight p : packetsNotCommitted) {
+ for (PacketInFlight p : packetsNotLogged) {
  fzk.logRequest(p.hdr, p.rec, p.digest);
  }
  for (Long zxid : packetsCommitted) {
@@ -792,7 +796,7 @@ protected void syncWithLeader(long newLeaderZxid) throws Exception {
  // Similar to follower, we need to log requests between the snapshot
  // and UPTODATE
  ObserverZooKeeperServer ozk = (ObserverZooKeeperServer) zk;
- for (PacketInFlight p : packetsNotCommitted) {
+ for (PacketInFlight p : packetsNotLogged) {
  Long zxid = packetsCommitted.peekFirst();
  if (p.hdr.getZxid() != zxid) {
  // log warning message if there is no matching commit

diff --git a/...eper-server/src/main/java/org/apache/zookeeper/server/quorum/SendAckRequestProcessor.java b/...eper-server/src/main/java/org/apache/zookeeper/server/quorum/SendAckRequestProcessor.java
@@ -66,7 +66,7 @@ public void flush() throws IOException {
  LOG.warn("Closing connection to leader, exception during packet send", e);
  try {
  Socket socket = learner.sock;
- if (socket != null && !learner.sock.isClosed()) {
+ if (socket != null && !socket.isClosed()) {
  learner.sock.close();
  }
  } catch (IOException e1) {