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Posted to users@activemq.apache.org by Eric-AWL <er...@atosorigin.com> on 2010/07/06 11:15:56 UTC

CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Hi

I'm sure that I identified a Latch problem in Multicast Network Discovery
mechanism on Duplex connection

The multicast notifier thread is blocked. here the trace

"Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
[0x0000000044c26000..0x0000000044c26b90]
   java.lang.Thread.State: WAITING (parking)
	at sun.misc.Unsafe.park(Native Method)
	- parking to wait for  <0x00002aaab3dd66f0> (a
java.util.concurrent.CountDownLatch$Sync)
	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
	at
java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
	at
java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
	at
java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
	at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
	at
org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
	at
org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
	at
org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
	at
java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
	at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
	at java.lang.Thread.run(Thread.java:619)

The problem appears when the network is quickly and alternatively on/off
between the two components.
The bridge is created in one direction, but the answer can not be received.

The thread is blocked on the CountDownLatch. Even if multicast frames are
received, the component can not establish a new network connection.

Here are an corresponding activemq trace 

When it is OK :
2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
- Establishing network connection from vm://SIBBusModule-NOCP5-tpnocp08s-bus
to tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge        
- Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160 and
tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
has been established.

2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge        
- SIBBusModule-NOCP5-tpnocp08s-bus bridge to SIBBusSupervisor-tpnocp11v-bus
stopped

2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
- Establishing network connection from vm://SIBBusModule-NOCP5-tpnocp08s-bus
to tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge        
- Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162 and
tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
has been established.

2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge        
- SIBBusModule-NOCP5-tpnocp08s-bus bridge to SIBBusSupervisor-tpnocp11v-bus
stopped

When it is KO : "Unknown" 

2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
- Establishing network connection from vm://SIBBusModule-NOCP5-tpnocp08s-bus
to tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge        
- Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164 and
tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due to a
remote error: java.net.SocketException: Connection reset
2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge        
- SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped


Here is the other side corresponding activemq trace 

activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO 
TransportConnection            - Created Duplex Bridge back to
SIBBusModule-NOCP5-tpnocp08s-bus

activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO 
DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
SIBBusModule-NOCP5-tpnocp08s-bus stopped

activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO 
TransportConnection            - Created Duplex Bridge back to
SIBBusModule-NOCP5-tpnocp08s-bus
activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO 
DemandForwardingBridge         - Network connection between
vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
established.

activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO 
DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
SIBBusModule-NOCP5-tpnocp08s-bus stopped

activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO 
TransportConnection            - Created Duplex Bridge back to
SIBBusModule-NOCP5-tpnocp08s-bus
activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO 
DemandForwardingBridge         - Network connection between
vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
established.

activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO 
DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
SIBBusModule-NOCP5-tpnocp08s-bus stopped


Eric-AWL
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Re: CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Eric-AWL <er...@atosorigin.com>.
I added a fix in the Jira AMQ-2774 thread.

Eric-AWL


Eric-AWL wrote:
> 
> We put a no-Duplex Configuration instead of a Duplex Configuration and it
> seemed to work better.... But
> today during a network problem (alternatively on/off) our process doesn't
> resist ....
> 
> We have 
> - a thread dump which shows 85 StartLocalBridge Threads waiting for the
> same latch into the DemandForwardingBridgeSupport.StartLocalBridge method
> :
> 
>  protected void startLocalBridge() throws Exception {
>         if (localBridgeStarted.compareAndSet(false, true)) {
>             synchronized (this) {
>                 if (LOG.isTraceEnabled()) {
>                     LOG.trace(configuration.getBrokerName() + " starting
> local Bridge, localBroker=" + localBroker);
>                 }
>                 remoteBrokerNameKnownLatch.await();
>                 ...
> }
> 
> - 960 CLOSE_WAIT
> - a file descriptor limit
> 
> Will the transport.closeAsync=false flag be helpful here ?
> 
> Eric-AWL
> 
> 
> 
> Gary Tully wrote:
>> 
>> Hi, as you can see, this is a complicated area of the code. The best
>> approach is to try and produce a test case for your scenario. Take a
>> look at the test: BrokerQueueNetworkWithDisconnectTest in
>> activemq-core. This can simulate network failures and can use
>> multicast (bridgeAllBrokers). Getting a reproducible test case is the
>> best way to validate your changes and protect them into the future.
>> 
>> The only other alternative is to keep adding your suggestions to the
>> jira issue (https://issues.apache.org/activemq/browse/AMQ-2774) and
>> with a bit of luck I (or some one else) will have a change to look at
>> it before 5.4 .
>> 
>> 
>> On 6 July 2010 12:37, Eric-AWL <er...@atosorigin.com> wrote:
>>>
>>> I wonder if it could not have some undesirable effects on both side of
>>> the
>>> duplex connection ....
>>>
>>> perhaps we should test the started AtomicBoolean, in the start() method
>>> after the corresponding "await" and shouldn't execute the end of the
>>> start
>>> method ?
>>>
>>>            if (configuration.isDuplex() && duplexInitiatingConnection ==
>>> null) {
>>>                // initiator side of duplex network
>>>                remoteBrokerNameKnownLatch.await();
>>>            }
>>>
>>> HERE ??? (if started.get()) { ???
>>>
>>>            try {
>>>                triggerRemoteStartBridge();
>>>            } catch (IOException e) {
>>>                LOG.warn("Caught exception from remote start", e);
>>>            }
>>>            NetworkBridgeListener l = this.networkBridgeListener;
>>>            if (l != null) {
>>>                l.onStart(this);
>>>            }
>>>
>>> It's the first big problem I have with ActiveMQ complex configuration,
>>> it
>>> happens when network is faulty (that happens not very often), and I
>>> don't
>>> know ActiveMQ source code very well ....
>>>
>>> Who could help me to identify potential effects of this change, before I
>>> try
>>> to modify it ? (I can't do that on my production system without some
>>> tests
>>> and expert validation)
>>>
>>> Eric-AWL
>>>
>>>
>>> Gary Tully wrote:
>>>>
>>>> that seems reasonable. want to submit a patch against trunk?
>>>>
>>>> On 6 July 2010 12:10, Eric-AWL <er...@atosorigin.com> wrote:
>>>>>
>>>>> What could happen if we add
>>>>>
>>>>>         if (configuration.isDuplex() && duplexInitiatingConnection ==
>>>>> null)
>>>>> {
>>>>>                // initiator side of duplex network
>>>>>                remoteBrokerNameKnownLatch.countDown();
>>>>>            }
>>>>>
>>>>> into the stop() method of DemandForwardingBridgeSupport class ?
>>>>>
>>>>> Eric-AWL
>>>>>
>>>>>
>>>>> Eric-AWL wrote:
>>>>>>
>>>>>> Hi
>>>>>>
>>>>>> I'm sure that I identified a Latch problem in Multicast Network
>>>>>> Discovery
>>>>>> mechanism on Duplex connection
>>>>>>
>>>>>> The multicast notifier thread is blocked. here the trace
>>>>>>
>>>>>> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
>>>>>> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
>>>>>> [0x0000000044c26000..0x0000000044c26b90]
>>>>>>    java.lang.Thread.State: WAITING (parking)
>>>>>>       at sun.misc.Unsafe.park(Native Method)
>>>>>>       - parking to wait for  <0x00002aaab3dd66f0> (a
>>>>>> java.util.concurrent.CountDownLatch$Sync)
>>>>>>       at
>>>>>> java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
>>>>>>       at
>>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
>>>>>>       at
>>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
>>>>>>       at
>>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
>>>>>>       at
>>>>>> java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
>>>>>>       at
>>>>>> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
>>>>>>       at
>>>>>> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
>>>>>>       at
>>>>>> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
>>>>>>       at
>>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
>>>>>>       at
>>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
>>>>>>       at java.lang.Thread.run(Thread.java:619)
>>>>>>
>>>>>> The problem appears when the network is quickly and alternatively
>>>>>> on/off
>>>>>> between the two components.
>>>>>> The bridge is created in one direction, but the answer can not be
>>>>>> received.
>>>>>>
>>>>>> The thread is blocked on the CountDownLatch. Even if multicast frames
>>>>>> are
>>>>>> received, the component can not establish a new network connection.
>>>>>>
>>>>>> Here are an corresponding activemq trace
>>>>>>
>>>>>> When it is OK :
>>>>>> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO
>>>>>>  DiscoveryNetworkConnector
>>>>>> - Establishing network connection from
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>>> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO
>>>>>>  DemandForwardingBridge
>>>>>> - Network connection between
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus#160
>>>>>> and
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>>>> has been established.
>>>>>>
>>>>>> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO
>>>>>>  DemandForwardingBridge
>>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>>>
>>>>>> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO
>>>>>>  DiscoveryNetworkConnector
>>>>>> - Establishing network connection from
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>>> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO
>>>>>>  DemandForwardingBridge
>>>>>> - Network connection between
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus#162
>>>>>> and
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>>>> has been established.
>>>>>>
>>>>>> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO
>>>>>>  DemandForwardingBridge
>>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>>>
>>>>>> When it is KO : "Unknown"
>>>>>>
>>>>>> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO
>>>>>>  DiscoveryNetworkConnector
>>>>>> - Establishing network connection from
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>>> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN
>>>>>>  DemandForwardingBridge
>>>>>> - Network connection between
>>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus#164
>>>>>> and
>>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due
>>>>>> to
>>>>>> a
>>>>>> remote error: java.net.SocketException: Connection reset
>>>>>> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO
>>>>>>  DemandForwardingBridge
>>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
>>>>>>
>>>>>>
>>>>>> Here is the other side corresponding activemq trace
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO
>>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO
>>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus
>>>>>> bridge
>>>>>> to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO
>>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>>> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO
>>>>>> DemandForwardingBridge         - Network connection between
>>>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
>>>>>> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>>>> established.
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO
>>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus
>>>>>> bridge
>>>>>> to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO
>>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>>> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO
>>>>>> DemandForwardingBridge         - Network connection between
>>>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
>>>>>> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>>>> established.
>>>>>>
>>>>>> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO
>>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus
>>>>>> bridge
>>>>>> to
>>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>>
>>>>>>
>>>>>> Eric-AWL
>>>>>>
>>>>>
>>>>> --
>>>>> View this message in context:
>>>>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084235.html
>>>>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>>>>
>>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> http://blog.garytully.com
>>>>
>>>> Open Source Integration
>>>> http://fusesource.com
>>>>
>>>>
>>>
>>> --
>>> View this message in context:
>>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084410.html
>>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>>
>>>
>> 
>> 
>> 
>> -- 
>> http://blog.garytully.com
>> 
>> Open Source Integration
>> http://fusesource.com
>> 
>> 
> 
> 

-- 
View this message in context: http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29236977.html
Sent from the ActiveMQ - User mailing list archive at Nabble.com.


Re: CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Eric-AWL <er...@atosorigin.com>.
We put a no-Duplex Configuration instead of a Duplex Configuration and it
seemed to work better.... But
today during a network problem (alternatively on/off) our process doesn't
resist ....

We have 
- a thread dump which shows 85 StartLocalBridge Threads waiting for the same
latch into the DemandForwardingBridgeSupport.StartLocalBridge method :

 protected void startLocalBridge() throws Exception {
        if (localBridgeStarted.compareAndSet(false, true)) {
            synchronized (this) {
                if (LOG.isTraceEnabled()) {
                    LOG.trace(configuration.getBrokerName() + " starting
local Bridge, localBroker=" + localBroker);
                }
                remoteBrokerNameKnownLatch.await();
                ...
}

- 960 CLOSE_WAIT
- a file descriptor limit

Will the transport.closeAsync=false flag be helpful here ?

Eric-AWL



Gary Tully wrote:
> 
> Hi, as you can see, this is a complicated area of the code. The best
> approach is to try and produce a test case for your scenario. Take a
> look at the test: BrokerQueueNetworkWithDisconnectTest in
> activemq-core. This can simulate network failures and can use
> multicast (bridgeAllBrokers). Getting a reproducible test case is the
> best way to validate your changes and protect them into the future.
> 
> The only other alternative is to keep adding your suggestions to the
> jira issue (https://issues.apache.org/activemq/browse/AMQ-2774) and
> with a bit of luck I (or some one else) will have a change to look at
> it before 5.4 .
> 
> 
> On 6 July 2010 12:37, Eric-AWL <er...@atosorigin.com> wrote:
>>
>> I wonder if it could not have some undesirable effects on both side of
>> the
>> duplex connection ....
>>
>> perhaps we should test the started AtomicBoolean, in the start() method
>> after the corresponding "await" and shouldn't execute the end of the
>> start
>> method ?
>>
>>            if (configuration.isDuplex() && duplexInitiatingConnection ==
>> null) {
>>                // initiator side of duplex network
>>                remoteBrokerNameKnownLatch.await();
>>            }
>>
>> HERE ??? (if started.get()) { ???
>>
>>            try {
>>                triggerRemoteStartBridge();
>>            } catch (IOException e) {
>>                LOG.warn("Caught exception from remote start", e);
>>            }
>>            NetworkBridgeListener l = this.networkBridgeListener;
>>            if (l != null) {
>>                l.onStart(this);
>>            }
>>
>> It's the first big problem I have with ActiveMQ complex configuration, it
>> happens when network is faulty (that happens not very often), and I don't
>> know ActiveMQ source code very well ....
>>
>> Who could help me to identify potential effects of this change, before I
>> try
>> to modify it ? (I can't do that on my production system without some
>> tests
>> and expert validation)
>>
>> Eric-AWL
>>
>>
>> Gary Tully wrote:
>>>
>>> that seems reasonable. want to submit a patch against trunk?
>>>
>>> On 6 July 2010 12:10, Eric-AWL <er...@atosorigin.com> wrote:
>>>>
>>>> What could happen if we add
>>>>
>>>>         if (configuration.isDuplex() && duplexInitiatingConnection ==
>>>> null)
>>>> {
>>>>                // initiator side of duplex network
>>>>                remoteBrokerNameKnownLatch.countDown();
>>>>            }
>>>>
>>>> into the stop() method of DemandForwardingBridgeSupport class ?
>>>>
>>>> Eric-AWL
>>>>
>>>>
>>>> Eric-AWL wrote:
>>>>>
>>>>> Hi
>>>>>
>>>>> I'm sure that I identified a Latch problem in Multicast Network
>>>>> Discovery
>>>>> mechanism on Duplex connection
>>>>>
>>>>> The multicast notifier thread is blocked. here the trace
>>>>>
>>>>> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
>>>>> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
>>>>> [0x0000000044c26000..0x0000000044c26b90]
>>>>>    java.lang.Thread.State: WAITING (parking)
>>>>>       at sun.misc.Unsafe.park(Native Method)
>>>>>       - parking to wait for  <0x00002aaab3dd66f0> (a
>>>>> java.util.concurrent.CountDownLatch$Sync)
>>>>>       at
>>>>> java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
>>>>>       at
>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
>>>>>       at
>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
>>>>>       at
>>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
>>>>>       at
>>>>> java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
>>>>>       at
>>>>> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
>>>>>       at
>>>>> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
>>>>>       at
>>>>> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
>>>>>       at
>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
>>>>>       at
>>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
>>>>>       at java.lang.Thread.run(Thread.java:619)
>>>>>
>>>>> The problem appears when the network is quickly and alternatively
>>>>> on/off
>>>>> between the two components.
>>>>> The bridge is created in one direction, but the answer can not be
>>>>> received.
>>>>>
>>>>> The thread is blocked on the CountDownLatch. Even if multicast frames
>>>>> are
>>>>> received, the component can not establish a new network connection.
>>>>>
>>>>> Here are an corresponding activemq trace
>>>>>
>>>>> When it is OK :
>>>>> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO
>>>>>  DiscoveryNetworkConnector
>>>>> - Establishing network connection from
>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge
>>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160
>>>>> and
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>>> has been established.
>>>>>
>>>>> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>>
>>>>> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO
>>>>>  DiscoveryNetworkConnector
>>>>> - Establishing network connection from
>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge
>>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162
>>>>> and
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>>> has been established.
>>>>>
>>>>> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>>
>>>>> When it is KO : "Unknown"
>>>>>
>>>>> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO
>>>>>  DiscoveryNetworkConnector
>>>>> - Establishing network connection from
>>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>>> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge
>>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164
>>>>> and
>>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due
>>>>> to
>>>>> a
>>>>> remote error: java.net.SocketException: Connection reset
>>>>> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge
>>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
>>>>>
>>>>>
>>>>> Here is the other side corresponding activemq trace
>>>>>
>>>>> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO
>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>>
>>>>> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO
>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>>> to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>
>>>>> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO
>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO
>>>>> DemandForwardingBridge         - Network connection between
>>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
>>>>> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>>> established.
>>>>>
>>>>> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO
>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>>> to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>
>>>>> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO
>>>>> TransportConnection            - Created Duplex Bridge back to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO
>>>>> DemandForwardingBridge         - Network connection between
>>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
>>>>> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>>> established.
>>>>>
>>>>> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO
>>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>>> to
>>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>>
>>>>>
>>>>> Eric-AWL
>>>>>
>>>>
>>>> --
>>>> View this message in context:
>>>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084235.html
>>>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> http://blog.garytully.com
>>>
>>> Open Source Integration
>>> http://fusesource.com
>>>
>>>
>>
>> --
>> View this message in context:
>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084410.html
>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>
>>
> 
> 
> 
> -- 
> http://blog.garytully.com
> 
> Open Source Integration
> http://fusesource.com
> 
> 

-- 
View this message in context: http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29098137.html
Sent from the ActiveMQ - User mailing list archive at Nabble.com.


Re: CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Gary Tully <ga...@gmail.com>.
Hi, as you can see, this is a complicated area of the code. The best
approach is to try and produce a test case for your scenario. Take a
look at the test: BrokerQueueNetworkWithDisconnectTest in
activemq-core. This can simulate network failures and can use
multicast (bridgeAllBrokers). Getting a reproducible test case is the
best way to validate your changes and protect them into the future.

The only other alternative is to keep adding your suggestions to the
jira issue (https://issues.apache.org/activemq/browse/AMQ-2774) and
with a bit of luck I (or some one else) will have a change to look at
it before 5.4 .


On 6 July 2010 12:37, Eric-AWL <er...@atosorigin.com> wrote:
>
> I wonder if it could not have some undesirable effects on both side of the
> duplex connection ....
>
> perhaps we should test the started AtomicBoolean, in the start() method
> after the corresponding "await" and shouldn't execute the end of the start
> method ?
>
>            if (configuration.isDuplex() && duplexInitiatingConnection ==
> null) {
>                // initiator side of duplex network
>                remoteBrokerNameKnownLatch.await();
>            }
>
> HERE ??? (if started.get()) { ???
>
>            try {
>                triggerRemoteStartBridge();
>            } catch (IOException e) {
>                LOG.warn("Caught exception from remote start", e);
>            }
>            NetworkBridgeListener l = this.networkBridgeListener;
>            if (l != null) {
>                l.onStart(this);
>            }
>
> It's the first big problem I have with ActiveMQ complex configuration, it
> happens when network is faulty (that happens not very often), and I don't
> know ActiveMQ source code very well ....
>
> Who could help me to identify potential effects of this change, before I try
> to modify it ? (I can't do that on my production system without some tests
> and expert validation)
>
> Eric-AWL
>
>
> Gary Tully wrote:
>>
>> that seems reasonable. want to submit a patch against trunk?
>>
>> On 6 July 2010 12:10, Eric-AWL <er...@atosorigin.com> wrote:
>>>
>>> What could happen if we add
>>>
>>>         if (configuration.isDuplex() && duplexInitiatingConnection ==
>>> null)
>>> {
>>>                // initiator side of duplex network
>>>                remoteBrokerNameKnownLatch.countDown();
>>>            }
>>>
>>> into the stop() method of DemandForwardingBridgeSupport class ?
>>>
>>> Eric-AWL
>>>
>>>
>>> Eric-AWL wrote:
>>>>
>>>> Hi
>>>>
>>>> I'm sure that I identified a Latch problem in Multicast Network
>>>> Discovery
>>>> mechanism on Duplex connection
>>>>
>>>> The multicast notifier thread is blocked. here the trace
>>>>
>>>> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
>>>> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
>>>> [0x0000000044c26000..0x0000000044c26b90]
>>>>    java.lang.Thread.State: WAITING (parking)
>>>>       at sun.misc.Unsafe.park(Native Method)
>>>>       - parking to wait for  <0x00002aaab3dd66f0> (a
>>>> java.util.concurrent.CountDownLatch$Sync)
>>>>       at
>>>> java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
>>>>       at
>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
>>>>       at
>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
>>>>       at
>>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
>>>>       at
>>>> java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
>>>>       at
>>>> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
>>>>       at
>>>> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
>>>>       at
>>>> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
>>>>       at
>>>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
>>>>       at
>>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
>>>>       at java.lang.Thread.run(Thread.java:619)
>>>>
>>>> The problem appears when the network is quickly and alternatively on/off
>>>> between the two components.
>>>> The bridge is created in one direction, but the answer can not be
>>>> received.
>>>>
>>>> The thread is blocked on the CountDownLatch. Even if multicast frames
>>>> are
>>>> received, the component can not establish a new network connection.
>>>>
>>>> Here are an corresponding activemq trace
>>>>
>>>> When it is OK :
>>>> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO
>>>>  DiscoveryNetworkConnector
>>>> - Establishing network connection from
>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge
>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160
>>>> and
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>> has been established.
>>>>
>>>> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>
>>>> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO
>>>>  DiscoveryNetworkConnector
>>>> - Establishing network connection from
>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge
>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162
>>>> and
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>>> has been established.
>>>>
>>>> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>>
>>>> When it is KO : "Unknown"
>>>>
>>>> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO
>>>>  DiscoveryNetworkConnector
>>>> - Establishing network connection from
>>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>>> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge
>>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164
>>>> and
>>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due to
>>>> a
>>>> remote error: java.net.SocketException: Connection reset
>>>> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge
>>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
>>>>
>>>>
>>>> Here is the other side corresponding activemq trace
>>>>
>>>> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO
>>>> TransportConnection            - Created Duplex Bridge back to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>>
>>>> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO
>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>> to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>
>>>> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO
>>>> TransportConnection            - Created Duplex Bridge back to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO
>>>> DemandForwardingBridge         - Network connection between
>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
>>>> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>> established.
>>>>
>>>> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO
>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>> to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>
>>>> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO
>>>> TransportConnection            - Created Duplex Bridge back to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO
>>>> DemandForwardingBridge         - Network connection between
>>>> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
>>>> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>>> established.
>>>>
>>>> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO
>>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>>> to
>>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>>
>>>>
>>>> Eric-AWL
>>>>
>>>
>>> --
>>> View this message in context:
>>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084235.html
>>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>>
>>>
>>
>>
>>
>> --
>> http://blog.garytully.com
>>
>> Open Source Integration
>> http://fusesource.com
>>
>>
>
> --
> View this message in context: http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084410.html
> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>
>



-- 
http://blog.garytully.com

Open Source Integration
http://fusesource.com

Re: CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Eric-AWL <er...@atosorigin.com>.
I wonder if it could not have some undesirable effects on both side of the
duplex connection ....

perhaps we should test the started AtomicBoolean, in the start() method
after the corresponding "await" and shouldn't execute the end of the start
method ?

            if (configuration.isDuplex() && duplexInitiatingConnection ==
null) {
                // initiator side of duplex network
                remoteBrokerNameKnownLatch.await();
            }

HERE ??? (if started.get()) { ???

            try {
                triggerRemoteStartBridge();
            } catch (IOException e) {
                LOG.warn("Caught exception from remote start", e);
            }
            NetworkBridgeListener l = this.networkBridgeListener;
            if (l != null) {
                l.onStart(this);
            }

It's the first big problem I have with ActiveMQ complex configuration, it
happens when network is faulty (that happens not very often), and I don't
know ActiveMQ source code very well .... 

Who could help me to identify potential effects of this change, before I try
to modify it ? (I can't do that on my production system without some tests
and expert validation)

Eric-AWL 


Gary Tully wrote:
> 
> that seems reasonable. want to submit a patch against trunk?
> 
> On 6 July 2010 12:10, Eric-AWL <er...@atosorigin.com> wrote:
>>
>> What could happen if we add
>>
>>         if (configuration.isDuplex() && duplexInitiatingConnection ==
>> null)
>> {
>>                // initiator side of duplex network
>>                remoteBrokerNameKnownLatch.countDown();
>>            }
>>
>> into the stop() method of DemandForwardingBridgeSupport class ?
>>
>> Eric-AWL
>>
>>
>> Eric-AWL wrote:
>>>
>>> Hi
>>>
>>> I'm sure that I identified a Latch problem in Multicast Network
>>> Discovery
>>> mechanism on Duplex connection
>>>
>>> The multicast notifier thread is blocked. here the trace
>>>
>>> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
>>> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
>>> [0x0000000044c26000..0x0000000044c26b90]
>>>    java.lang.Thread.State: WAITING (parking)
>>>       at sun.misc.Unsafe.park(Native Method)
>>>       - parking to wait for  <0x00002aaab3dd66f0> (a
>>> java.util.concurrent.CountDownLatch$Sync)
>>>       at
>>> java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
>>>       at
>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
>>>       at
>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
>>>       at
>>> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
>>>       at
>>> java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
>>>       at
>>> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
>>>       at
>>> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
>>>       at
>>> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
>>>       at
>>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
>>>       at
>>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
>>>       at java.lang.Thread.run(Thread.java:619)
>>>
>>> The problem appears when the network is quickly and alternatively on/off
>>> between the two components.
>>> The bridge is created in one direction, but the answer can not be
>>> received.
>>>
>>> The thread is blocked on the CountDownLatch. Even if multicast frames
>>> are
>>> received, the component can not establish a new network connection.
>>>
>>> Here are an corresponding activemq trace
>>>
>>> When it is OK :
>>> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO
>>>  DiscoveryNetworkConnector
>>> - Establishing network connection from
>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge
>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160
>>> and
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>> has been established.
>>>
>>> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>
>>> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO
>>>  DiscoveryNetworkConnector
>>> - Establishing network connection from
>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge
>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162
>>> and
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>>> has been established.
>>>
>>> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>>> SIBBusSupervisor-tpnocp11v-bus stopped
>>>
>>> When it is KO : "Unknown"
>>>
>>> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO
>>>  DiscoveryNetworkConnector
>>> - Establishing network connection from
>>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>>> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge
>>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164
>>> and
>>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due to
>>> a
>>> remote error: java.net.SocketException: Connection reset
>>> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge
>>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
>>>
>>>
>>> Here is the other side corresponding activemq trace
>>>
>>> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO
>>> TransportConnection            - Created Duplex Bridge back to
>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>>
>>> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO
>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>> to
>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>
>>> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO
>>> TransportConnection            - Created Duplex Bridge back to
>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO
>>> DemandForwardingBridge         - Network connection between
>>> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
>>> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>> established.
>>>
>>> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO
>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>> to
>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>
>>> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO
>>> TransportConnection            - Created Duplex Bridge back to
>>> SIBBusModule-NOCP5-tpnocp08s-bus
>>> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO
>>> DemandForwardingBridge         - Network connection between
>>> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
>>> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>>> established.
>>>
>>> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO
>>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge
>>> to
>>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>>
>>>
>>> Eric-AWL
>>>
>>
>> --
>> View this message in context:
>> http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084235.html
>> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>>
>>
> 
> 
> 
> -- 
> http://blog.garytully.com
> 
> Open Source Integration
> http://fusesource.com
> 
> 

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Re: CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Gary Tully <ga...@gmail.com>.
that seems reasonable. want to submit a patch against trunk?

On 6 July 2010 12:10, Eric-AWL <er...@atosorigin.com> wrote:
>
> What could happen if we add
>
>         if (configuration.isDuplex() && duplexInitiatingConnection == null)
> {
>                // initiator side of duplex network
>                remoteBrokerNameKnownLatch.countDown();
>            }
>
> into the stop() method of DemandForwardingBridgeSupport class ?
>
> Eric-AWL
>
>
> Eric-AWL wrote:
>>
>> Hi
>>
>> I'm sure that I identified a Latch problem in Multicast Network Discovery
>> mechanism on Duplex connection
>>
>> The multicast notifier thread is blocked. here the trace
>>
>> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
>> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
>> [0x0000000044c26000..0x0000000044c26b90]
>>    java.lang.Thread.State: WAITING (parking)
>>       at sun.misc.Unsafe.park(Native Method)
>>       - parking to wait for  <0x00002aaab3dd66f0> (a
>> java.util.concurrent.CountDownLatch$Sync)
>>       at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
>>       at
>> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
>>       at
>> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
>>       at
>> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
>>       at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
>>       at
>> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
>>       at
>> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
>>       at
>> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
>>       at
>> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
>>       at
>> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
>>       at java.lang.Thread.run(Thread.java:619)
>>
>> The problem appears when the network is quickly and alternatively on/off
>> between the two components.
>> The bridge is created in one direction, but the answer can not be
>> received.
>>
>> The thread is blocked on the CountDownLatch. Even if multicast frames are
>> received, the component can not establish a new network connection.
>>
>> Here are an corresponding activemq trace
>>
>> When it is OK :
>> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector
>> - Establishing network connection from
>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge
>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160 and
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>> has been established.
>>
>> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>> SIBBusSupervisor-tpnocp11v-bus stopped
>>
>> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector
>> - Establishing network connection from
>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge
>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162 and
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
>> has been established.
>>
>> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge
>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
>> SIBBusSupervisor-tpnocp11v-bus stopped
>>
>> When it is KO : "Unknown"
>>
>> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector
>> - Establishing network connection from
>> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
>> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge
>> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164 and
>> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due to a
>> remote error: java.net.SocketException: Connection reset
>> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge
>> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
>>
>>
>> Here is the other side corresponding activemq trace
>>
>> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO
>> TransportConnection            - Created Duplex Bridge back to
>> SIBBusModule-NOCP5-tpnocp08s-bus
>>
>> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO
>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>
>> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO
>> TransportConnection            - Created Duplex Bridge back to
>> SIBBusModule-NOCP5-tpnocp08s-bus
>> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO
>> DemandForwardingBridge         - Network connection between
>> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
>> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>> established.
>>
>> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO
>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>
>> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO
>> TransportConnection            - Created Duplex Bridge back to
>> SIBBusModule-NOCP5-tpnocp08s-bus
>> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO
>> DemandForwardingBridge         - Network connection between
>> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
>> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
>> established.
>>
>> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO
>> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
>> SIBBusModule-NOCP5-tpnocp08s-bus stopped
>>
>>
>> Eric-AWL
>>
>
> --
> View this message in context: http://old.nabble.com/MultiCast-Discovery-and-refusal-of-connection-tp28827529p29084235.html
> Sent from the ActiveMQ - User mailing list archive at Nabble.com.
>
>



-- 
http://blog.garytully.com

Open Source Integration
http://fusesource.com

CountDownLatch problem . MultiCast Discovery and refusal of connection on DUPLEX connection (Fuse 5.3.0.5) .

Posted by Eric-AWL <er...@atosorigin.com>.
What could happen if we add

         if (configuration.isDuplex() && duplexInitiatingConnection == null)
{
                // initiator side of duplex network
                remoteBrokerNameKnownLatch.countDown();
            }

into the stop() method of DemandForwardingBridgeSupport class ?

Eric-AWL


Eric-AWL wrote:
> 
> Hi
> 
> I'm sure that I identified a Latch problem in Multicast Network Discovery
> mechanism on Duplex connection
> 
> The multicast notifier thread is blocked. here the trace
> 
> "Notifier-MulticastDiscoveryAgent-listener:DiscoveryNetworkConnector:NOCSupervisorP5-ADMIN-OUT-IN:BrokerService[SIBBusModule-NOCP5-tpnocp08s-bus]"
> daemon prio=10 tid=0x0000000044ff2400 nid=0x1389 waiting on condition
> [0x0000000044c26000..0x0000000044c26b90]
>    java.lang.Thread.State: WAITING (parking)
> 	at sun.misc.Unsafe.park(Native Method)
> 	- parking to wait for  <0x00002aaab3dd66f0> (a
> java.util.concurrent.CountDownLatch$Sync)
> 	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
> 	at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:747)
> 	at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:905)
> 	at
> java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1217)
> 	at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
> 	at
> org.apache.activemq.network.DemandForwardingBridgeSupport.start(DemandForwardingBridgeSupport.java:231)
> 	at
> org.apache.activemq.network.DiscoveryNetworkConnector.onServiceAdd(DiscoveryNetworkConnector.java:114)
> 	at
> org.apache.activemq.transport.discovery.multicast.MulticastDiscoveryAgent$2.run(MulticastDiscoveryAgent.java:484)
> 	at
> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
> 	at
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
> 	at java.lang.Thread.run(Thread.java:619)
> 
> The problem appears when the network is quickly and alternatively on/off
> between the two components.
> The bridge is created in one direction, but the answer can not be
> received.
> 
> The thread is blocked on the CountDownLatch. Even if multicast frames are
> received, the component can not establish a new network connection.
> 
> Here are an corresponding activemq trace 
> 
> When it is OK :
> 2010-06-22 22:56:24,500 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
> - Establishing network connection from
> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
> 2010-06-22 22:56:26,083 [nocp08s-bus#160] INFO  DemandForwardingBridge        
> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#160 and
> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
> has been established.
> 
> 2010-06-22 22:57:34,807 [-tpnocp08s-bus]] INFO  DemandForwardingBridge        
> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
> SIBBusSupervisor-tpnocp11v-bus stopped
> 
> 2010-06-22 22:57:34,811 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
> - Establishing network connection from
> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
> 2010-06-22 22:57:39,064 [nocp08s-bus#162] INFO  DemandForwardingBridge        
> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#162 and
> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101(SIBBusSupervisor-tpnocp11v-bus)
> has been established.
> 
> 2010-06-22 22:58:42,578 [-tpnocp08s-bus]] INFO  DemandForwardingBridge        
> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to
> SIBBusSupervisor-tpnocp11v-bus stopped
> 
> When it is KO : "Unknown" 
> 
> 2010-06-22 22:58:42,648 [-tpnocp08s-bus]] INFO  DiscoveryNetworkConnector     
> - Establishing network connection from
> vm://SIBBusModule-NOCP5-tpnocp08s-bus to
> tcp://tpnocp11v-bus.vdm.priv.amm.noc:14101?useLocalHost=false
> 2010-06-22 22:59:18,031 [18.126.30:14101] WARN  DemandForwardingBridge        
> - Network connection between vm://SIBBusModule-NOCP5-tpnocp08s-bus#164 and
> tcp://tpnocp11v-bus.vdm.priv.amm.noc/10.18.126.30:14101 shutdown due to a
> remote error: java.net.SocketException: Connection reset
> 2010-06-22 22:59:18,033 [NetworkBridge  ] INFO  DemandForwardingBridge        
> - SIBBusModule-NOCP5-tpnocp08s-bus bridge to Unknown stopped
> 
> 
> Here is the other side corresponding activemq trace 
> 
> activemq-server.log:2010-06-22 22:55:44,295 [26.190.27:40517] INFO 
> TransportConnection            - Created Duplex Bridge back to
> SIBBusModule-NOCP5-tpnocp08s-bus
> 
> activemq-server.log:2010-06-22 22:56:24,438 [26.190.27:40517] INFO 
> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
> SIBBusModule-NOCP5-tpnocp08s-bus stopped
> 
> activemq-server.log:2010-06-22 22:56:26,135 [26.190.27:40518] INFO 
> TransportConnection            - Created Duplex Bridge back to
> SIBBusModule-NOCP5-tpnocp08s-bus
> activemq-server.log:2010-06-22 22:56:26,135 [ocp11v-bus#1770] INFO 
> DemandForwardingBridge         - Network connection between
> vm://SIBBusSupervisor-tpnocp11v-bus#1770 and
> tcp:///10.26.190.27:40518(SIBBusModule-NOCP5-tpnocp08s-bus) has been
> established.
> 
> activemq-server.log:2010-06-22 22:57:34,818 [26.190.27:40518] INFO 
> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
> SIBBusModule-NOCP5-tpnocp08s-bus stopped
> 
> activemq-server.log:2010-06-22 22:57:39,153 [26.190.27:40519] INFO 
> TransportConnection            - Created Duplex Bridge back to
> SIBBusModule-NOCP5-tpnocp08s-bus
> activemq-server.log:2010-06-22 22:57:39,153 [ocp11v-bus#1806] INFO 
> DemandForwardingBridge         - Network connection between
> vm://SIBBusSupervisor-tpnocp11v-bus#1806 and
> tcp:///10.26.190.27:40519(SIBBusModule-NOCP5-tpnocp08s-bus) has been
> established.
> 
> activemq-server.log:2010-06-22 22:58:44,328 [26.190.27:40519] INFO 
> DemandForwardingBridge         - SIBBusSupervisor-tpnocp11v-bus bridge to
> SIBBusModule-NOCP5-tpnocp08s-bus stopped
> 
> 
> Eric-AWL
> 

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