Date: Sat, 23 Jun 2012 11:04:33 -0700 (PDT)
From: Yaron Naveh <yaron...@gmail.com>
To: neo4j@googlegroups.com
Message-Id: <37aa1a34-1c74-4fbb-87a4-1ceca873a6ef@googlegroups.com>
Subject: errors on delete
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Hi

I'm using neo4j 1.8 using node-neo4j (which uses the REST api of neo4j).

I need to delete 100 nodes. When I do this synchronously there is no 
problem (e.g. I wait for one delete to finish before calling the next one).
When I delete them in an async manner (many rest requests sent 
concurrently) I intermittently get a few failures. I see this coming back 
in the http response once per each error:

HTTP/1.1 500 Transaction(15744)[STATUS_ACTIVE,Resources=1] can't wait on 
resource RWLock[Relationship[8253]] since => 
Transaction(15744)[STATUS_ACTIVE,Resources=1] <-[:HELD_BY]- 
RWLock[Node[1841]] <-[:WAITING_FOR]- 
Transaction(15744)[STATUS_ACTIVE,Resources=1] <-[:HELD_BY]- 
RWLock[Relationship[8253]]
Content-Length: 0
Server: Jetty(6.1.25)

I believe neo4j uses keep-alive to reuse the same connection but this does 
not seem relevant. I have verified my code is (logically) correct, e.g. I 
do not delete an already deleted node and etc.

Any idea?

Thanks,
Yaron

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<div>Hi</div><div><br></div><div>I'm using neo4j 1.8 using node-neo4j (whic=
h uses the REST api of neo4j).</div><div><br></div><div>I need to delete 10=
0 nodes. When I do this&nbsp;synchronously&nbsp;there is no problem (e.g. I=
 wait for one delete to finish before calling the next one).</div><div>When=
 I delete them in an async manner (many rest requests sent concurrently) I&=
nbsp;intermittently&nbsp;get a few failures. I see this coming back in the =
http response once per each error:</div><div><br></div><div>HTTP/1.1 500 Tr=
ansaction(15744)[STATUS_ACTIVE,Resources=3D1] can't wait on resource RWLock=
[Relationship[8253]] since =3D&gt; Transaction(15744)[STATUS_ACTIVE,Resourc=
es=3D1] &lt;-[:HELD_BY]- RWLock[Node[1841]] &lt;-[:WAITING_FOR]- Transactio=
n(15744)[STATUS_ACTIVE,Resources=3D1] &lt;-[:HELD_BY]- RWLock[Relationship[=
8253]]</div><div>Content-Length: 0</div><div>Server: Jetty(6.1.25)</div><di=
v><br></div><div>I&nbsp;believe&nbsp;neo4j uses keep-alive to reuse the sam=
e connection but this does not seem relevant. I have verified my code is (l=
ogically) correct, e.g. I do not delete an already deleted node and etc.</d=
iv><div><br></div><div>Any idea?</div><div><br></div><div>Thanks,</div><div=
>Yaron</div>
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