From 680f84b5a28b8f1af85640a32c2c0b936a890d5a Mon Sep 17 00:00:00 2001 From: Andy Taylor Date: Tue, 6 Sep 2016 11:49:23 +0100 Subject: [PATCH] ARTEMIS-742 = replication quorum broken https://issues.apache.org/jira/browse/ARTEMIS-742 --- .../qourum/QuorumVoteServerConnect.java | 47 ++++++++++--------- .../qourum/SharedNothingBackupQuorum.java | 2 +- 2 files changed, 25 insertions(+), 24 deletions(-) diff --git a/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/QuorumVoteServerConnect.java b/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/QuorumVoteServerConnect.java index 79e41ee384..352e5e34f3 100644 --- a/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/QuorumVoteServerConnect.java +++ b/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/QuorumVoteServerConnect.java @@ -31,35 +31,35 @@ public class QuorumVoteServerConnect extends QuorumVote { private static final SimpleString LIVE_FAILOVER_VOTE = new SimpleString("LIVE_FAILOVER)VOTE"); private final CountDownLatch latch; - private double votesNeeded; + private int votesNeeded; private int total = 0; private boolean decision = false; /** - * vote the remaining nodes not including ourself., so - * 1 remaining nodes would be 0/2 = 0 vote needed - * 2 remaining nodes would be 1/2 = 0 vote needed - * 3 remaining nodes would be 2/2 = 1 vote needed - * 4 remaining nodes would be 3/2 = 2 vote needed - * 5 remaining nodes would be 4/2 = 3 vote needed - * 6 remaining nodes would be 5/2 = 3 vote needed + * live nodes | remaining nodes | majority | votes needed + * 1 | 0 | 0 | 0 + * 2 | 1 | 1 | 1 + * n | r = n-1 | n/2 + 1 | n/2 + 1 rounded + * 3 | 2 | 2.5 | 2 + * 4 | 3 | 3 | 3 + * 5 | 4 | 3.5 | 3 + * 6 | 5 | 4 | 4 */ public QuorumVoteServerConnect(int size, StorageManager storageManager) { super(LIVE_FAILOVER_VOTE); - //we don't count ourself - int actualSize = size - 1; - if (actualSize <= 2) { - votesNeeded = actualSize / 2; + double majority; + if (size <= 2) { + majority = ((double)size) / 2; } else { //even - votesNeeded = actualSize / 2 + 1; + majority = ((double)size) / 2 + 1; } //votes needed could be say 2.5 so we add 1 in this case - int latchSize = votesNeeded > (int) votesNeeded ? (int) votesNeeded + 1 : (int) votesNeeded; - latch = new CountDownLatch(latchSize); + votesNeeded = (int) majority; + latch = new CountDownLatch(votesNeeded); if (votesNeeded == 0) { decision = true; } @@ -86,13 +86,14 @@ public class QuorumVoteServerConnect extends QuorumVote { } /** - * vote the remaining nodes not including ourself., so - * 1 remaining nodes would be 0/2 = 0 vote needed - * 2 remaining nodes would be 1/2 = 0 vote needed - * 3 remaining nodes would be 2/2 = 1 vote needed - * 4 remaining nodes would be 3/2 = 2 vote needed - * 5 remaining nodes would be 4/2 = 3 vote needed - * 6 remaining nodes would be 5/2 = 3 vote needed + * live nodes | remaining nodes | majority | votes needed + * 1 | 0 | 0 | 0 + * 2 | 1 | 1 | 1 + * n | r = n-1 | n/2 + 1 | n/2 + 1 rounded + * 3 | 2 | 2.5 | 2 + * 4 | 3 | 3 | 3 + * 5 | 4 | 3.5 | 3 + * 6 | 5 | 4 | 4 * * @param vote the vote to make. */ @@ -102,9 +103,9 @@ public class QuorumVoteServerConnect extends QuorumVote { return; if (vote.getVote()) { total++; + latch.countDown(); if (total >= votesNeeded) { decision = true; - latch.countDown(); } } } diff --git a/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/SharedNothingBackupQuorum.java b/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/SharedNothingBackupQuorum.java index c1bf6a860f..5a95791119 100644 --- a/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/SharedNothingBackupQuorum.java +++ b/artemis-server/src/main/java/org/apache/activemq/artemis/core/server/cluster/qourum/SharedNothingBackupQuorum.java @@ -252,7 +252,7 @@ public class SharedNothingBackupQuorum implements Quorum, SessionFailureListener */ private boolean isLiveDown() { // we use 1 less than the max cluste size as we arent bothered about the replicated live node - int size = quorumManager.getMaxClusterSize() - 1; + int size = quorumManager.getMaxClusterSize(); QuorumVoteServerConnect quorumVote = new QuorumVoteServerConnect(size, storageManager);