search

br1ghtyang / asterixdb

Automatically exported from code.google.com/p/asterixdb
0 stars 0 forks source link

Concurrent scan of INTERNAL & Metadata datasets throws NPE #510

Closed GoogleCodeExporter closed 8 years ago

GoogleCodeExporter commented 8 years ago 
What steps will reproduce the problem?

This NPE is seen on latest code base of asterix master that uses hyracks 
master. Here is the latest commit available in asterix master from git log

kfmohamm@khurram:~/asterixdb_release/asterixdb$ git log
commit c9df3d191619909e501202669572db02be166064
Author: Madhusudan.C.S <madhusudancs@gmail.com>
Date:   Wed Jun 5 17:40:00 2013 -0700

    Update the API port number in docs.

Create asterix instance using managix (one CC and NC) and run the attached 
concurrency test java program from Eclipse, and you will see the following 
Exception in your cc.log under managix directory. The NPE shown below is seen 
while scanning most Metadata datasets. Thread pool size being 16.

I do a scan of all Metadata Datasets from ConcurrencyTest.java

Jun 05, 2013 8:03:05 PM 
edu.uci.ics.hyracks.algebricks.core.rewriter.base.HeuristicOptimizer optimize
INFO: Optimized Plan:
distribute result [%0->$$0]
-- DISTRIBUTE_RESULT  |PARTITIONED|
  exchange
  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
    project ([$$0])
    -- STREAM_PROJECT  |PARTITIONED|
      exchange
      -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
        data-scan []<-[$$2, $$3, $$4, $$0] <- Metadata:Function
        -- DATASOURCE_SCAN  |PARTITIONED|
          exchange
          -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
            empty-tuple-source
            -- EMPTY_TUPLE_SOURCE  |PARTITIONED|

Jun 05, 2013 8:03:05 PM 
edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper mkRecordDescriptor
WARNING: No type for variable $$2
java.lang.NullPointerException
WARNING: No type for variable $$2
java.lang.NullPointerException
        at edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider.getSerializerDeserializer(AqlSerializerDeserializerProvider.java:72)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper.mkRecordDescriptor(JobGenHelper.java:58)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildBtreeRuntime(AqlMetadataProvider.java:515)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildInternalDatasetScan(AqlMetadataProvider.java:326)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.getScannerRuntime(AqlMetadataProvider.java:303)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.DataSourceScanPOperator.contributeRuntimeOperator(DataSourceScanPOperator.java:82)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator.contributeRuntimeOperator(AbstractLogicalOperator.java:157)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:91)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compilePlan(PlanCompiler.java:54)
        at edu.uci.ics.hyracks.algebricks.compiler.api.HeuristicCompilerFactoryBuilder$1$1.createJob(HeuristicCompilerFactoryBuilder.java:98)
        at edu.uci.ics.asterix.api.common.APIFramework.compileQuery(APIFramework.java:351)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.rewriteCompileQuery(AqlTranslator.java:1293)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.handleQuery(AqlTranslator.java:1387)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.compileAndExecute(AqlTranslator.java:279)
        at edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet.doGet(RESTAPIServlet.java:98)
        at edu.uci.ics.asterix.api.http.servlet.QueryAPIServlet.doGet(QueryAPIServlet.java:25)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:734)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:546)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:483)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:970)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:411)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:904)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)
        at org.eclipse.jetty.server.Server.handle(Server.java:347)
        at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:439)
        at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:907)
        at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:562)
        at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214)
        at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:43)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529)
        at java.lang.Thread.run(Thread.java:722)

Original issue reported on code.google.com by khfaraaz82 on 6 Jun 2013 at 3:20

Attachments:

GoogleCodeExporter commented 8 years ago 
Is it metadata only?

Original comment by buyingyi@gmail.com on 6 Jun 2013 at 3:23

GoogleCodeExporter commented 8 years ago 
For now, I tried this concurrency test to scan Metadata Datasets only. I have 
not tried this concurrency test program on internal datasets. It can be used to 
run concurrent scans on internal datasets too, those that are created by users..

PS: Thanks to Madhusudhan for having reviewed and helped me in refining my 
concurrency test program.

Original comment by khfaraaz82 on 6 Jun 2013 at 3:39

GoogleCodeExporter commented 8 years ago 
Can you add the test as part of the build tests in your private branch?

Original comment by buyingyi@gmail.com on 6 Jun 2013 at 3:42

GoogleCodeExporter commented 8 years ago 
Yes, I can do that. Addressing review comments for my thesis now.
I will definitely add this test to my branch, once those comments are addressed.

Original comment by khfaraaz82 on 6 Jun 2013 at 3:45

GoogleCodeExporter commented 8 years ago 
Similar NPEs are also seen when scanning Index and Dataverse metadata datasets.

Jun 05, 2013 8:03:05 PM 
edu.uci.ics.hyracks.algebricks.core.rewriter.base.HeuristicOptimizer optimize
INFO: Optimized Plan:
distribute result [%0->$$0]
-- DISTRIBUTE_RESULT  |PARTITIONED|
  exchange
  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
    project ([$$0])
    -- STREAM_PROJECT  |PARTITIONED|
      exchange
      -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
        data-scan []<-[$$2, $$0] <- Metadata:Dataverse
        -- DATASOURCE_SCAN  |PARTITIONED|
          exchange
          -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
            empty-tuple-source
            -- EMPTY_TUPLE_SOURCE  |PARTITIONED|

Jun 05, 2013 8:03:05 PM edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet 
doGet
SEVERE: null
java.lang.NullPointerException
Jun 05, 2013 8:03:05 PM edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet 
doGet
SEVERE: null
java.lang.NullPointerException
        at edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider.getSerializerDeserializer(AqlSerializerDeserializerProvider.java:72)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper.mkRecordDescriptor(JobGenHelper.java:58)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildBtreeRuntime(AqlMetadataProvider.java:515)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildInternalDatasetScan(AqlMetadataProvider.java:326)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.getScannerRuntime(AqlMetadataProvider.java:303)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.DataSourceScanPOperator.contributeRuntimeOperator(DataSourceScanPOperator.java:82)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator.contributeRuntimeOperator(AbstractLogicalOperator.java:157)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:91)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compilePlan(PlanCompiler.java:54)
        at edu.uci.ics.hyracks.algebricks.compiler.api.HeuristicCompilerFactoryBuilder$1$1.createJob(HeuristicCompilerFactoryBuilder.java:98)
        at edu.uci.ics.asterix.api.common.APIFramework.compileQuery(APIFramework.java:351)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.rewriteCompileQuery(AqlTranslator.java:1293)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.handleQuery(AqlTranslator.java:1387)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.compileAndExecute(AqlTranslator.java:279)
        at edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet.doGet(RESTAPIServlet.java:98)
        at edu.uci.ics.asterix.api.http.servlet.QueryAPIServlet.doGet(QueryAPIServlet.java:25)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:734)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:546)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:483)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:970)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:411)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:904)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)
        at org.eclipse.jetty.server.Server.handle(Server.java:347)
        at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:439)
        at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:907)
        at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:562)
        at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214)
        at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:43)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529)
        at java.lang.Thread.run(Thread.java:722)

....

Jun 05, 2013 8:03:06 PM 
edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper mkRecordDescriptor
WARNING: No type for variable $$2
Jun 05, 2013 8:03:06 PM 
edu.uci.ics.hyracks.algebricks.core.rewriter.base.HeuristicOptimizer optimize
INFO: Optimized Plan:
distribute result [%0->$$0]
-- DISTRIBUTE_RESULT  |PARTITIONED|
  exchange
  -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
    project ([$$0])
    -- STREAM_PROJECT  |PARTITIONED|
      exchange
      -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
        data-scan []<-[$$2, $$3, $$4, $$0] <- Metadata:Index
        -- DATASOURCE_SCAN  |PARTITIONED|
          exchange
          -- ONE_TO_ONE_EXCHANGE  |PARTITIONED|
            empty-tuple-source
            -- EMPTY_TUPLE_SOURCE  |PARTITIONED|

java.lang.NullPointerException
java.lang.NullPointerException
        at edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider.getSerializerDeserializer(AqlSerializerDeserializerProvider.java:72)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper.mkRecordDescriptor(JobGenHelper.java:58)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildBtreeRuntime(AqlMetadataProvider.java:515)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildInternalDatasetScan(AqlMetadataProvider.java:326)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.getScannerRuntime(AqlMetadataProvider.java:303)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.DataSourceScanPOperator.contributeRuntimeOperator(DataSourceScanPOperator.java:82)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator.contributeRuntimeOperator(AbstractLogicalOperator.java:157)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:91)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compilePlan(PlanCompiler.java:54)
        at edu.uci.ics.hyracks.algebricks.compiler.api.HeuristicCompilerFactoryBuilder$1$1.createJob(HeuristicCompilerFactoryBuilder.java:98)
        at edu.uci.ics.asterix.api.common.APIFramework.compileQuery(APIFramework.java:351)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.rewriteCompileQuery(AqlTranslator.java:1293)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.handleQuery(AqlTranslator.java:1387)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.compileAndExecute(AqlTranslator.java:279)
        at edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet.doGet(RESTAPIServlet.java:98)
        at edu.uci.ics.asterix.api.http.servlet.QueryAPIServlet.doGet(QueryAPIServlet.java:25)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:734)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:546)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:483)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:970)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:411)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:904)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)
        at org.eclipse.jetty.server.Server.handle(Server.java:347)
        at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:439)
        at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:907)
        at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:562)
        at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214)
        at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:43)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529)
        at java.lang.Thread.run(Thread.java:722)

Original comment by khfaraaz82 on 6 Jun 2013 at 3:46

GoogleCodeExporter commented 8 years ago 
Concurrent scans of internal datasets also leads to NPE as reported above. The 
stack trace for the NPE in the cc log is exactly similar to the one above. To 
reproduce, please run these AQL statements from Web UI and then run the 
WisconsinScan.java program from Eclipse, and you will see the NPE in cc.log 
under managix directory.

The data is generated as per Wisconsin benchmark and the queries used to run 
concurrently are also from that benchmark.

drop dataverse test if exists;
create dataverse test;
use dataverse test;

create type Schema as closed {
unique1:  int32,
unique2:  int32,
two: int32,
four: int32,
ten: int32,
twenty:  int32,
onePercent: int32,
tenPercent:  int32,
twentyPercent:  int32,
fiftyPercent:  int32,
unique3:  int32,
evenOnePercent: int32,
oddOnePercent:  int32,
stringu1:  string,
stringu2:  string,
string4:  string
}

create dataset tenktup1(Schema) primary key unique2 ;

load dataset tenktup1 using localfs
(("path"="localhost:///home/kfmohamm/data-gen/one-mil-tup.adm"),("format"="delim
ited-text"),("delimiter"="|")) pre-sorted;

Here is the stack trace from cc.log

Jun 07, 2013 5:47:59 PM 
edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper mkRecordDescriptor
WARNING: No type for variable $$2
java.lang.NullPointerException
        at edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider.getSerializerDeserializer(AqlSerializerDeserializerProvider.java:72)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.JobGenHelper.mkRecordDescriptor(JobGenHelper.java:58)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildBtreeRuntime(AqlMetadataProvider.java:515)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.buildInternalDatasetScan(AqlMetadataProvider.java:326)
        at edu.uci.ics.asterix.metadata.declared.AqlMetadataProvider.getScannerRuntime(AqlMetadataProvider.java:303)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.physical.DataSourceScanPOperator.contributeRuntimeOperator(DataSourceScanPOperator.java:82)
        at edu.uci.ics.hyracks.algebricks.core.algebra.operators.logical.AbstractLogicalOperator.contributeRuntimeOperator(AbstractLogicalOperator.java:157)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:91)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compileOpRef(PlanCompiler.java:78)
        at edu.uci.ics.hyracks.algebricks.core.jobgen.impl.PlanCompiler.compilePlan(PlanCompiler.java:54)
        at edu.uci.ics.hyracks.algebricks.compiler.api.HeuristicCompilerFactoryBuilder$1$1.createJob(HeuristicCompilerFactoryBuilder.java:98)
        at edu.uci.ics.asterix.api.common.APIFramework.compileQuery(APIFramework.java:351)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.rewriteCompileQuery(AqlTranslator.java:1293)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.handleQuery(AqlTranslator.java:1387)
        at edu.uci.ics.asterix.aql.translator.AqlTranslator.compileAndExecute(AqlTranslator.java:279)
        at edu.uci.ics.asterix.api.http.servlet.RESTAPIServlet.doGet(RESTAPIServlet.java:98)
        at edu.uci.ics.asterix.api.http.servlet.QueryAPIServlet.doGet(QueryAPIServlet.java:25)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:734)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
        at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:546)
        at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:483)
        at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:231)
        at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:970)
        at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:411)
        at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:192)
        at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:904)
        at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:117)
        at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:110)
        at org.eclipse.jetty.server.Server.handle(Server.java:347)
        at org.eclipse.jetty.server.HttpConnection.handleRequest(HttpConnection.java:439)
        at org.eclipse.jetty.server.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:907)
        at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:562)
        at org.eclipse.jetty.http.HttpParser.parseAvailable(HttpParser.java:214)
        at org.eclipse.jetty.server.AsyncHttpConnection.handle(AsyncHttpConnection.java:43)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint.handle(SelectChannelEndPoint.java:545)
        at org.eclipse.jetty.io.nio.SelectChannelEndPoint$1.run(SelectChannelEndPoint.java:43)
        at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:529)
        at java.lang.Thread.run(Thread.java:722)

Original comment by khfaraaz82 on 8 Jun 2013 at 1:19

Attachments:

GoogleCodeExporter commented 8 years ago

Original comment by khfaraaz82 on 10 Jun 2013 at 6:35

GoogleCodeExporter commented 8 years ago 
Is this issue being investigated ?

Original comment by khfaraaz82 on 18 Jun 2013 at 9:59

GoogleCodeExporter commented 8 years ago 
I am yet to find the exact cause

Original comment by ram...@uci.edu on 18 Jun 2013 at 10:09

GoogleCodeExporter commented 8 years ago 
Yingyi - this says "concurrent" - should you take this one?

Original comment by dtab...@gmail.com on 27 Jun 2013 at 4:48

GoogleCodeExporter commented 8 years ago 
With the new transactions system in place now. Can someone please run this test 
to verify. This was a concurrency test that was giving NPE's. 
Thanks.

Original comment by khfaraaz82 on 6 Nov 2013 at 4:39

GoogleCodeExporter commented 8 years ago 
I have found the source of the issue. 
The source is as follows. 
During concurrent query compilations, a datatype object cached in 
MetadataManager is accessed by those compilers. The datatype object has an 
ARecordType object in it and the ARecordType object has UTF8StringPointable 
object in it. The problem occurs when the UTF8StringPointable.compare() is 
called since the UTF8StringPointable is not stateless, so UTF8StringPointable 
object in the ARecordType object (which is in the datatype object) shows the 
problem when it is called concurrently.

One possible solution can be creating a new comparator for UTF8Sting which is 
STATELESS. 
Or, simply we can copy the datatype object in the metdataManager's cache when 
the datatype object is returned to the caller.

Please your opinion or suggestions. 

Young-Seok

Original comment by kiss...@gmail.com on 20 Nov 2013 at 9:02

GoogleCodeExporter commented 8 years ago

Original comment by kiss...@gmail.com on 21 Nov 2013 at 10:47