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https://issues.apache.org/jira/browse/AMBARI-11394?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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John Speidel updated AMBARI-11394:
----------------------------------
    Description: 
Provisioning a cluster may occasionally fail to complete as a result of an out 
of order database write.

This error presents itself as start task(s) that never progresses beyond the 
PENDING state.  For these logical pending tasks, there are no associated 
physical tasks.

When a host is matched to a host request, an install request is submitted 
followed immediately by a start request.  The install task transitions all host 
components desired_state for the host from INIT to INSTALLED.  But, because of 
an error in the persistence layer, after the desired_state is set to INSTALLED, 
it is overwritten on another thread (heartbeat handler thread) to INIT.  As a 
result, the component is never started because it it's desired state is INIT 
and isn't processed by the start operation.

The root cause of this is that  the public method 
ServiceComponentHostImpl.handleEvent() is annotated with '@Transactional'.  
Inside of this method the proper locks are acquired, BUT because this method is 
marked as @Transactional it's invocation is wrapped in a proxy which wraps the 
method invocation in a transaction.  As a result, the transaction is committed 
in the proxy after the method returns outside of any synchronization which 
allows for out of order writes.  

  was:
Provisioning a cluster may occasionally fail to complete as a result of an out 
of order database write.

This error presents itself as start task(s) that never progresses beyond the 
PENDING state.  For these logical pending tasks, there are no associated 
physical tasks.

When a host is matched to a host request, an install request is submitted 
followed immediately by a start request.  The install task transitions all host 
components desired_state for the host from INIT to INSTALLED.  But, because of 
an error in the persistence layer, after the desired_state is set to INSTALLED, 
it is overwritten on another thread (heartbeat handler thread) to INIT.  As a 
result, the component is never started because it it's desired state is INIT 
and isn't processed by the start operation.

The root cause of this is that  the public method 
ServiceComponentHostImpl.handleEvent() is annotated with '@Transactional'.  
Inside of this method the proper locks are acquired, BUT because this method is 
marked as @Transactional it's invocation is wrapped in a proxy which starts and 
commits a transaction around the method.  As a result, the transaction is 
committed in the proxy outside of any synchronization which allows for out of 
order writes.  


> Blueprint cluster provision occasionally fails due to out of order database 
> writes
> ----------------------------------------------------------------------------------
>
>                 Key: AMBARI-11394
>                 URL: https://issues.apache.org/jira/browse/AMBARI-11394
>             Project: Ambari
>          Issue Type: Bug
>    Affects Versions: 2.1.0
>            Reporter: John Speidel
>            Assignee: John Speidel
>             Fix For: 2.1.0
>
>
> Provisioning a cluster may occasionally fail to complete as a result of an 
> out of order database write.
> This error presents itself as start task(s) that never progresses beyond the 
> PENDING state.  For these logical pending tasks, there are no associated 
> physical tasks.
> When a host is matched to a host request, an install request is submitted 
> followed immediately by a start request.  The install task transitions all 
> host components desired_state for the host from INIT to INSTALLED.  But, 
> because of an error in the persistence layer, after the desired_state is set 
> to INSTALLED, it is overwritten on another thread (heartbeat handler thread) 
> to INIT.  As a result, the component is never started because it it's desired 
> state is INIT and isn't processed by the start operation.
> The root cause of this is that  the public method 
> ServiceComponentHostImpl.handleEvent() is annotated with '@Transactional'.  
> Inside of this method the proper locks are acquired, BUT because this method 
> is marked as @Transactional it's invocation is wrapped in a proxy which wraps 
> the method invocation in a transaction.  As a result, the transaction is 
> committed in the proxy after the method returns outside of any 
> synchronization which allows for out of order writes.  



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