home list archives users mailing list
 

Subject: RE: Tomcat OutOfMemoryError with OGSA-DAI clients

Date view Thread view Subject view Author view Attachment view

From: Ally Hume (a.hume@epcc.ed.ac.uk)
Date: May 16, 2006 09:55

Hi Lucas,

It does sound like the client is a fault here.

Let's start with the simple stuff first! Have you increased the
memory heap size for the client? Your notes seem to imply you have
done this only for the server.

It sounds like you get the error when just using the data browser or
end to end client to talk to OGSA-DAI. In this case increasing the
memory of the server and/or the client should remove the out of memory
error.

What exactly is the error you are seeing on the client? Do you have a
full stack trace?

Regards,

Ally

-------------------------------------------------------------
Ally Hume
Software Architect
EPCC, University of Edinburgh
James Clerk Maxwell Building
Mayfield Road E-mail: a.hume@epcc.ed.ac.uk
Edinburgh, EH9 3JZ Phone: + 44 (0) 131 651 3397
United Kingdom Fax: + 44 (0) 131 650 6555
-------------------------------------------------------------

-----Original Message-----
From: owner-users@ogsadai.org.uk [mailto:owner-users@ogsadai.org.uk]
On Behalf Of Lucas Zamboulis
Sent: 12 May 2006 21:31
To: users@ogsadai.org.uk
Subject: Tomcat OutOfMemoryError with OGSA-DAI clients

Hi,

I'm having trouble retrieving a 200,000 integer result set from a
MySQL
database. I'm using OGSA-DAI WSI 2.1 on a Linux FC4 with 2GB RAM. I
successfully retrieve data from other tables in the same DB (and from
the same table when e.g. adding an Id<1000 constraint on the query).
This is therefore a problem having to do with the size of the result
set: both databrowser and end-to-end client exit with an
OutOfMemoryError, although the Tomcat log (see end of mail) .

I then read the related issue in the DAI FAQ, which suggests:

- increase the memory heap size for the virtual machine using the
Xms<size> flag.
--- Done that, raised both Xms and Xmx flags in the catalina.sh file,
using both CATALINA_OPTS and JAVA_OPTS, problem persists

- may be a JDBC driver issue for specific db (loading whole results
set
in memory prior to giving a handle to DAI), try using another DBMS
--- Using the latest driver, DBMS: MySQL version 4.1.

- Try using asynchronous data transport functionalty to stream the
data
to and from the service in chunks
--- I'm actually trying to use DQP over DAI, so it's out of my
control,
but as I understand it, DQP 3 does use asynchronous data transport
functionalty and I still get an error when issuing the same query on
DQP
(that's how I first noticed the problem - although the problem appears

in a different manner when using DQP).

Do you think the error I'm getting is because neither the databrowser,

nor the end-to-end client use asynchronous data transport? I'm asking
because the start of the log file (showing all three DAI process to
have
completed successfully) implies that DAI successfully processed the
query and the result set, and therefore the error may be in the
application using DAI.

If not, any ideas?

Regards,
Lucas

----------------------------------------------------------------------
-
Lucas Zamboulis
R.A./Ph.D. candidate
School of Computer Science and Information Systems
Birkbeck College, University of London
London Knowledge Lab Tel.: +44 20 7763 2102
23-29 Emerald Street Fax: +44 20 7242 2756
London, WC1N 3QS http://www.dcs.bbk.ac.uk/~lucas

May 12, 2006 9:17:33 PM org.apache.catalina.startup.Catalina start
INFO: Server startup in 4814 ms
- statementOutputStatus : PROCESSING
- statementRSToXMLStatus : PROCESSING
- statementStatus : PROCESSING
- statementStatus : COMPLETED
- statementRSToXMLStatus : COMPLETED
- statementOutputStatus : COMPLETED
- java.io.IOException:
ClientAbortException: java.net.SocketException: Connection reset
        at
org.apache.coyote.tomcat5.OutputBuffer.realWriteBytes(OutputBuffer.jav
a:373)
        at
org.apache.tomcat.util.buf.ByteChunk.append(ByteChunk.java:294)
        at
org.apache.coyote.tomcat5.OutputBuffer.writeBytes(OutputBuffer.java:40
1)
        at
org.apache.coyote.tomcat5.OutputBuffer.write(OutputBuffer.java:388)
        at
org.apache.coyote.tomcat5.CoyoteOutputStream.write(CoyoteOutputStream.
java:76)
        at org.apache.axis.utils.ByteArray.writeTo(ByteArray.java:375)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:265)
        at org.apache.axis.Message.writeTo(Message.java:528)
        at
org.apache.axis.transport.http.AxisServlet.sendResponse(AxisServlet.ja
va:902)
        at
org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:777
)
        at
javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
        at
org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase
.java:327)
        at
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
        at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Appli
cationFilterChain.java:237)
        at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFi
lterChain.java:157)
        at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperVa
lve.java:214)
        at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValve
Context.java:104)
        at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java
:520)
        at
org.apache.catalina.core.StandardContextValve.invokeInternal(StandardC
ontextValve.java:198)
        at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextVa
lve.java:152)
        at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValve
Context.java:104)
        at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java
:520)
        at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.ja
va:137)
        at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValve
Context.java:104)
        at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.ja
va:118)
        at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValve
Context.java:102)
        at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java
:520)
        at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValv
e.java:109)
        at
org.apache.catalina.core.StandardValveContext.invokeNext(StandardValve
Context.java:104)
        at
org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java
:520)
        at
org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
        at
org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160
)
        at
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:
799)
        at
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.proces
sConnection(Http11Protocol.java:705)
        at
org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:
577)
        at
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPo
ol.java:683)
        at java.lang.Thread.run(Thread.java:534)

Date view Thread view Subject view Author view Attachment view