Re: [Bigdata-developers] After a timeout I get only timeouts

[Daniel H. <da...@de...>]

I found another issue on this. When I stopped the server it prints 
several InterruptedExceptions, one for each of the queries that give a 
timeout.

     ERROR: BigdataRDFServlet.java:214:
     cause=java.lang.InterruptedException, query=SPARQL-QUERY:
     queryStr=PREFIX wikibase:<http://wikiba.se/ontology-beta#>
     PREFIX wd: <http://www.wikidata.org/entity/>  SELECT ?s ?p ?q ?qo  WHERE { { ?s
     ?p ?c . ?c ?ps wd:Q16533 . ?p wikibase:propertyValue ?ps . }
     OPTIONAL { ?c ?q ?qo . ?q a wikibase:Propert
     y . } } LIMIT 10000
     java.lang.InterruptedException

I have set timeout=60 in the request. That is, parametrically the 
request is:

"#{@endpoint}?query=#{url_encode(query)}&timeout=60&analytic=true"

It seems that the timeout is not working because tasks continue several 
minutes after the timeout.

Then, I also set a timeout in a file override.xml

<?xml version="1.0" encoding="UTF-8"?>
   <web-app xmlns="http://java.sun.com/xml/ns/javaee"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd"
          version="3.1">
   <display-name>Bigdata</display-name>
   <description>Bigdata</description>
   <context-param>
     <description></description>
     <param-name>queryTimeout</param-name>
     <param-value>2</param-value>
   </context-param>
</web-app>

Then, I run the server with

java -Xmx10g -Xms10g -XX:PermSize=10g -XX:MaxPermSize=10g 
-XX:+UseConcMarkSweepGC -XX:ParallelCMSThreads=5 
-Djetty.overrideWebXml=override.xml 
-Dbigdata.propertyFile=server.properties -jar blazegraph.jar

Then, several queries where aborted by the server. That is, the response 
have a status code 500 and the server prints this:

Go to http://172.17.69.182:9999/blazegraph/ to get started.
WARN : Haltable.java:466: com.bigdata.util.concurrent.Haltable@bd8c9ab : 
isFirstCause=true : com.bigdata.bop.engine.QueryTimeoutException: Query 
deadline is expired.
com.bigdata.bop.engine.QueryTimeoutException: Query deadline is expired.
         at com.bigdata.bop.engine.RunState.checkDeadline(RunState.java:832)
         at com.bigdata.bop.engine.RunState.startOp(RunState.java:753)
         at 
com.bigdata.bop.engine.AbstractRunningQuery.startOp(AbstractRunningQuery.java:789)
         at 
com.bigdata.bop.engine.QueryEngine.startOp(QueryEngine.java:1348)
         at 
com.bigdata.bop.engine.ChunkedRunningQuery$ChunkTaskWrapper.run(ChunkedRunningQuery.java:883)
         at 
java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
         at java.util.concurrent.FutureTask.run(FutureTask.java:262)
         at com.bigdata.concurrent.FutureTaskMon.run(FutureTaskMon.java:63)
         at 
com.bigdata.bop.engine.ChunkedRunningQuery$ChunkFutureTask.run(ChunkedRunningQuery.java:792)
         at 
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
         at 
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
         at java.lang.Thread.run(Thread.java:745)
ERROR: BigdataRDFServlet.java:214: 
cause=java.util.concurrent.ExecutionException: 
java.util.concurrent.ExecutionException: 
org.openrdf.query.QueryInterruptedException: ja
va.lang.RuntimeException: java.util.concurrent.ExecutionException: 
java.lang.RuntimeException: java.util.concurrent.ExecutionException: 
com.bigdata.bop.engine.QueryTimeou
tException: Query deadline is expired., query=SPARQL-QUERY: 
queryStr=PREFIX wikibase: <http://wikiba.se/ontology-beta#> PREFIX wd: 
<http://www.wikidata.org/entity/>  SELE
CT ?s ?p ?q ?qo  WHERE { { ?s ?p ?c . ?c ?ps wd:Q17912672 . ?p 
wikibase:propertyValue ?ps . } OPTIONAL { ?c ?q ?qo . ?q a 
wikibase:Property . } } LIMIT 10000
java.util.concurrent.ExecutionException: 
java.util.concurrent.ExecutionException: 
org.openrdf.query.QueryInterruptedException: java.lang.RuntimeException: 
java.util.concu
rrent.ExecutionException: java.lang.RuntimeException: 
java.util.concurrent.ExecutionException: 
com.bigdata.bop.engine.QueryTimeoutException: Query deadline is expired.

Thus, it seems that the timeout was working. However, after some 
queries, I got a timeout in the client. After this first timeout every 
query is answered with a timeout.

Cheers,
Daniel