Then that's something else.

Would you be able to create a minimal test-case that reproduces that?

Michael

> Am 31.03.2015 um 15:26 schrieb Matias Burak <[email protected]>:
> 
> Yes, I can. It happens every time I do a stress test. If I do the same 
> process for only one user it works fine and it closes all the transactions. 
> But doing it for 10 users it starts to do some long transactions (10 secs) in 
> different threads and I start to see locks (i also see some deadlocks that i 
> retry but locks are still there) and transactions are not closed. 
> 
>> El 31/3/2015, a las 10:19, Michael Hunger <[email protected] 
>> <mailto:[email protected]>> escribió:
>> 
>> So far it's deadlock detection is pretty good it uses a graph internally to 
>> do that (find cycles).
>> 
>> Do you think you could reproduce the situation somehow
>> 
>> Michael
>> 
>> 
>>> Am 30.03.2015 um 15:44 schrieb Matias Burak <[email protected] 
>>> <mailto:[email protected]>>:
>>> 
>>> Could it be possible that neo4j is not detecting a deadlock with more than 
>>> 2 threads?
>>> I mean this case: thread-1 needs something from thread-2 which needs 
>>> something from thread-3 which needs something from thread-1.
>>> 
>>> 
>>>> El 27/3/2015, a las 16:07, Michael Hunger 
>>>> <[email protected] 
>>>> <mailto:[email protected]>> escribió:
>>>> 
>>>> 
>>>>> Am 27.03.2015 um 17:24 schrieb Matias Burak <[email protected] 
>>>>> <mailto:[email protected]>>:
>>>>> 
>>>>> Thanks for your response.
>>>>> Yeah, it seems that transactions might not be closed. Why would this 
>>>>> happen? I mean... I’m doing my transactions on a Spring 
>>>>> TransactionTemplate execute.
>>>> 
>>>> Good question, don't know where the leak would come from.
>>>> Do you perhaps execute cypher or index queries without exhausting the 
>>>> results or calling .close on them?
>>>> 
>>>> But your stack traces should give you a hint.
>>>> 
>>>>> Do I need neo4j enterprise to check open transacctionn with JMX?
>>>> 
>>>> Yes
>>>> 
>>>>> A thread-dump look like this:
>>>>> 
>>>>> "pool-11537-thread-1" prio=5 tid=0x00007f930b395800 nid=0x1a36f in 
>>>>> Object.wait() [0x000000013c924000]
>>>>>    java.lang.Thread.State: WAITING (on object monitor)
>>>>>   at java.lang.Object.wait(Native Method)
>>>>>   - waiting on <0x00000006d6669c88> (a 
>>>>> org.neo4j.kernel.impl.transaction.RWLock)
>>>>>   at java.lang.Object.wait(Object.java:503)
>>>>>   at 
>>>>> org.neo4j.kernel.impl.transaction.RWLock.deadlockGuardedWait(RWLock.java:652)
>>>>>   at 
>>>>> org.neo4j.kernel.impl.transaction.RWLock.acquireWriteLock(RWLock.java:344)
>>>>> 
>>>>> nid=0x1a36f is the nid on the db? There’s no nid 107375 (decimal for 
>>>>> 0x1a36f)
>>>> 
>>>> 
>>>>> 
>>>>>  
>>>>>> El 27/3/2015, a las 12:54, Michael Hunger 
>>>>>> <[email protected] 
>>>>>> <mailto:[email protected]>> escribió:
>>>>>> 
>>>>>> Hi Matias, please send questions like that to the google group.
>>>>>> 
>>>>>> A deadlock appears when it is about to acquire two locks in reverse 
>>>>>> order.
>>>>>> 
>>>>>> What you see is probably just a lock that is not released because the 
>>>>>> transaction which created it was not closed and is still running?
>>>>>> 
>>>>>> You can check via JMX if there is still an ongoing open transaction and 
>>>>>> open locks.
>>>>>> 
>>>>>> Also when you take a thread-dump you see what lock (incl. node-id) the 
>>>>>> thread is waiting for.
>>>>>> 
>>>>>> Cheers, Michael
>>>>>> 
>>>>>> On Fri, Mar 27, 2015 at 4:07 PM, Matias Burak <[email protected] 
>>>>>> <mailto:[email protected]>> wrote:
>>>>>> Hi Michael, sorry I bother you again with another problem.
>>>>>> 
>>>>>> Is it possible that Neo4j doesn’t realize that it’s in a deadlock? I’m 
>>>>>> using an old version of the db (1.9) and when running several 
>>>>>> transactions on different threads against the db sometimes the threads 
>>>>>> get locked and never are released and I don’t see an exception, they are 
>>>>>> just stuck on deadlockGuardedWait().
>>>>>> I expect deadlocks and I built a retry feature to try again, but I’m not 
>>>>>> getting any exceptions :( (sometimes I am)
>>>>>> Any idea?
>>>>>> 
>>>>>> Thanks,
>>>>>> MAtias.
>>>>>> 
>>>>>> 
>>>>>> 
>>>>> 
>>>> 
>>> 
>> 
> 

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