java - 配置 Hazelcast CPSubsystem 重试超时

Question

目前我在 CPSubsystem 中注册了三个实例。

      ----- 
     | I1* | * Leader
      ----- 

 ----       ---- 
| I2 |     | I3 |
 ----       ---- 

当所有实例都启动运行、全部注册并在 CPSubsystem 上相互查看时，一切都按预期工作。以下调用用于在所有实例之间执行分布式锁:

getHazelcastInstance().getCpSubsystem().getLock(lockDefinition.getLockEntryName())

当其中两个实例死亡，并且没有领导者或其他实例可用于执行领导者选举时，我注意到一个问题:

      ----- 
     | XXX | * DEAD
      ----- 

 ----       ----- 
| I2 |     | XXX | * DEAD
 ----       ----- 

然后，正在运行的实例尝试获取分布式锁，但请求在执行getLock方法时被卡住，导致请求排队几分钟(需要配置实例变为时的超时时间)子系统中唯一的一个)。

我还注意到以下日志会永远打印:

2019-08-16 10:56:21.697  WARN 1337 --- [ration.thread-1] Impl$LeaderFailureDetectionTask(default) : [127.0.0.1]:5702 [dev] [3.12.1] We are FOLLOWER and there is no current leader. Will start new election round...
2019-08-16 10:56:23.737  WARN 1337 --- [cached.thread-8] c.h.nio.tcp.TcpIpConnectionErrorHandler  : [127.0.0.1]:5702 [dev] [3.12.1] Removing connection to endpoint [127.0.0.1]:5701 Cause => java.net.SocketException {Connection refused to address /127.0.0.1:5701}, Error-Count: 106
2019-08-16 10:56:23.927  WARN 1337 --- [ration.thread-1] Impl$LeaderFailureDetectionTask(default) : [127.0.0.1]:5702 [dev] [3.12.1] We are FOLLOWER and there is no current leader. Will start new election round...
2019-08-16 10:56:26.006  WARN 1337 --- [onMonitorThread] c.h.s.i.o.impl.Invocation                : [127.0.0.1]:5702 [dev] [3.12.1] Retrying invocation: Invocation{op=com.hazelcast.cp.internal.operation.ChangeRaftGroupMembershipOp{serviceName='hz:core:raft', identityHash=1295439737, partitionId=81, replicaIndex=0, callId=1468, invocationTime=1565963786004 (2019-08-16 10:56:26.004), waitTimeout=-1, callTimeout=60000, groupId=CPGroupId{name='default', seed=0, commitIndex=6}, membersCommitIndex=0, member=CPMember{uuid=4792972d-d430-48f5-93ed-cb0e1fd8aed2, address=[127.0.0.1]:5703}, membershipChangeMode=REMOVE}, tryCount=250, tryPauseMillis=500, invokeCount=130, callTimeoutMillis=60000, firstInvocationTimeMs=1565963740657, firstInvocationTime='2019-08-16 10:55:40.657', lastHeartbeatMillis=0, lastHeartbeatTime='1969-12-31 21:00:00.000', target=[127.0.0.1]:5701, pendingResponse={VOID}, backupsAcksExpected=0, backupsAcksReceived=0, connection=null}, Reason: com.hazelcast.core.MemberLeftException: Member [127.0.0.1]:5702 - ab45ea09-c8c9-4f03-b3db-42b7b440d161 this has left cluster!
2019-08-16 10:56:26.232  WARN 1337 --- [cached.thread-8] c.h.nio.tcp.TcpIpConnectionErrorHandler  : [127.0.0.1]:5702 [dev] [3.12.1] Removing connection to endpoint [127.0.0.1]:5701 Cause => java.net.SocketException {Connection refused to address /127.0.0.1:5701}, Error-Count: 107
2019-08-16 10:56:26.413  WARN 1337 --- [ration.thread-1] Impl$LeaderFailureDetectionTask(default) : [127.0.0.1]:5702 [dev] [3.12.1] We are FOLLOWER and there is no current leader. Will start new election round...
2019-08-16 10:56:27.143  WARN 1337 --- [onMonitorThread] c.h.s.i.o.impl.Invocation                : [127.0.0.1]:5702 [dev] [3.12.1] Retrying invocation: Invocation{op=com.hazelcast.cp.internal.operation.ChangeRaftGroupMembershipOp{serviceName='hz:core:raft', identityHash=1295439737, partitionId=81, replicaIndex=0, callId=1479, invocationTime=1565963787142 (2019-08-16 10:56:27.142), waitTimeout=-1, callTimeout=60000, groupId=CPGroupId{name='default', seed=0, commitIndex=6}, membersCommitIndex=0, member=CPMember{uuid=4792972d-d430-48f5-93ed-cb0e1fd8aed2, address=[127.0.0.1]:5703}, membershipChangeMode=REMOVE}, tryCount=250, tryPauseMillis=500, invokeCount=140, callTimeoutMillis=60000, firstInvocationTimeMs=1565963740657, firstInvocationTime='2019-08-16 10:55:40.657', lastHeartbeatMillis=0, lastHeartbeatTime='1969-12-31 21:00:00.000', target=[127.0.0.1]:5703, pendingResponse={VOID}, backupsAcksExpected=0, backupsAcksReceived=0, connection=null}, Reason: com.hazelcast.spi.exception.TargetNotMemberException: Not Member! target: CPMember{uuid=4792972d-d430-48f5-93ed-cb0e1fd8aed2, address=[127.0.0.1]:5703}, partitionId: 81, operation: com.hazelcast.cp.internal.operation.ChangeRaftGroupMembershipOp, service: hz:core:raft
2019-08-16 10:56:28.835  WARN 1337 --- [cached.thread-6] c.h.nio.tcp.TcpIpConnectionErrorHandler  : [127.0.0.1]:5702 [dev] [3.12.1] Removing connection to endpoint [127.0.0.1]:5701 Cause => java.net.SocketException {Connection refused to address /127.0.0.1:5701}, Error-Count: 108
2019-08-16 10:56:28.941  WARN 1337 --- [ration.thread-1] Impl$LeaderFailureDetectionTask(default) : [127.0.0.1]:5702 [dev] [3.12.1] We are FOLLOWER and there is no current leader. Will start new election round...
2019-08-16 10:56:31.038  WARN 1337 --- [cached.thread-3] c.h.nio.tcp.TcpIpConnectionErrorHandler  : [127.0.0.1]:5702 [dev] [3.12.1] Removing connection to endpoint [127.0.0.1]:5701 Cause => java.net.SocketException {Connection refused to address /127.0.0.1:5701}, Error-Count: 109
2019-08-16 10:56:31.533  WARN 1337 --- [ration.thread-1] Impl$LeaderFailureDetectionTask(default) : [127.0.0.1]:5702 [dev] [3.12.1] We are FOLLOWER and there is no current leader. Will start new election round...
2019-08-16 10:56:31.555  WARN 1337 --- [.async.thread-3] c.h.s.i.o.impl.Invocation                : [127.0.0.1]:5702 [dev] [3.12.1] Retrying invocation: Invocation{op=com.hazelcast.cp.internal.operation.ChangeRaftGroupMembershipOp{serviceName='hz:core:raft', identityHash=1295439737, partitionId=81, replicaIndex=0, callId=1493, invocationTime=1565963791554 (2019-08-16 10:56:31.554), waitTimeout=-1, callTimeout=60000, groupId=CPGroupId{name='default', seed=0, commitIndex=6}, membersCommitIndex=0, member=CPMember{uuid=4792972d-d430-48f5-93ed-cb0e1fd8aed2, address=[127.0.0.1]:5703}, membershipChangeMode=REMOVE}, tryCount=250, tryPauseMillis=500, invokeCount=150, callTimeoutMillis=60000, firstInvocationTimeMs=1565963740657, firstInvocationTime='2019-08-16 10:55:40.657', lastHeartbeatMillis=0, lastHeartbeatTime='1969-12-31 21:00:00.000', target=[127.0.0.1]:5702, pendingResponse={VOID}, backupsAcksExpected=0, backupsAcksReceived=0, connection=null}, Reason: com.hazelcast.cp.exception.NotLeaderException: CPMember{uuid=ab45ea09-c8c9-4f03-b3db-42b7b440d161, address=[127.0.0.1]:5702} is not LEADER of CPGroupId{name='default', seed=0, commitIndex=6}. Known leader is: N/A

有没有办法确定实例现在正在单独运行，如果是这样，在获取新锁期间不要阻塞应用程序？

我正在寻找某种机制来不以任何方式阻止应用程序的流程，即使应用程序单独运行，我也会使用常规的j.u.c.l.ReentrantLock而不是FencedLock.

Answer 1

CP 子系统旨在当没有足够的成员可用于首先形成 CP 子系统时，阻止对属于 CP 子系统系列的数据结构的所有操作。该属性由CPSubsystemConfig.setCPMemberCount(int)

控制

hazelcastInstance.getCPSubsystem().getCPSubsystemManagementService().getCPMembers() 将为您提供集群中的 CP 成员。

要确定集群成员计数，您可以使用 hazelcastInstance.getCluster().getMembers() 和/或使用 MembershipListener 来记录成员加入或离开事件。