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I have two fuseki. I'm trying to get some data from one fuseki and send it to another one. The query I'm using is like:

SELECT ?g ?s ?p ?o WHERE { GRAPH ?g { ?s ?p ?o } GRAPH ?g { ?s <mo:metric> "metricA"^^<http://www.w3.org/2001/XMLSchema#string> } }

I got a lot of data which is for metricA, then I send each of them by:

accessor.add(graph,model))

In order to speed up the process, I use the Executors.newCachedThreadPool to create many threads to send them.

Here comes the problem, I notice sending some metric has no problem even if interval I send them is only 100ms. However, for some other metrics after some time, the fuseki server will be unresponsive. Even if I try to access the web gui, I cannot get anything. BUT, if I stop sending the data at that time, the interesting thing is that fuseki begings to receive a lot of messages. It seems somehow it's blocked before.

Does any one what could be the problem?

Elsa Jiu
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    Which version of Fuseki are you using? Fuseki1 uses jetty8 with BlockingChannelConnector. This has been known to freeze if the client can send in parallel faster than the server can cope with requests. SelectChannelConnector does not exhibit the same issue but is less efficient for large updates. You can use it via a custom jetty configuration or build from source. Fuseki2 uses Jetty9 which does not exhibit the same issue. – AndyS Mar 08 '15 at 11:12
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    SELECT ?g ?s ?p ?o WHERE { GRAPH ?g { ?s "metricA"^^ } BIND ( AS ?p) BIND("metricA"^^ AS ?o) } is more efficient. – AndyS Mar 08 '15 at 11:18
  • Hi, thanks for the comments! I'm using the Fuseki 1.1.1, which I believe is Fuseki1, right? In this case let me try with Fuseki2 and your query. Thanks! – Elsa Jiu Mar 09 '15 at 11:36
  • Sorry, but where can I download the fuseki2? – Elsa Jiu Mar 09 '15 at 11:39
  • @weikun It's not listed on the website yet, you can get it from http://apache.petsads.us/jena/binaries/ . – Joshua Taylor Mar 09 '15 at 13:37
  • It's available as a development build at the moment. A release is in progress. – AndyS Mar 10 '15 at 11:52

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