Hi ,
I had already the exact same test program, which never failed or
blocked... But your answer combined with Eddie's answer gave me a new
angle to apprehend the issue.
The framework releases the CAS when it has finished the processing, but
nobody release the CAS if something went wrong when you send the CAS to
the queue. In my case , I have non XML character in some documents... I
got the following exception, and the CAS were never released....
org.xml.sax.SAXParseException: Trying to serialize non-XML 1.0
character: , 0x1f
at
org.apache.uima.util.XMLSerializer$CharacterValidatingContentHandler.checkForInvalidXmlChars(XMLSerializer.java:235)
at
org.apache.uima.util.XMLSerializer$CharacterValidatingContentHandler.startElement(XMLSerializer.java:155)
at
org.apache.uima.cas.impl.XmiCasSerializer$XmiCasDocSerializer.startElement(XmiCasSerializer.java:986)
at
org.apache.uima.cas.impl.XmiCasSerializer$XmiCasDocSerializer.encodeFS(XmiCasSerializer.java:739)
at
org.apache.uima.cas.impl.XmiCasSerializer$XmiCasDocSerializer.encodeIndexed(XmiCasSerializer.java:684)
at
org.apache.uima.cas.impl.XmiCasSerializer$XmiCasDocSerializer.serialize(XmiCasSerializer.java:268)
at
org.apache.uima.cas.impl.XmiCasSerializer$XmiCasDocSerializer.access$700(XmiCasSerializer.java:108)
at
org.apache.uima.cas.impl.XmiCasSerializer.serialize(XmiCasSerializer.java:1522)
at
org.apache.uima.aae.UimaSerializer.serializeCasToXmi(UimaSerializer.java:136)
at
org.apache.uima.adapter.jms.client.BaseUIMAAsynchronousEngineCommon_impl.serializeCAS(BaseUIMAAsynchronousEngineCommon_impl.java:259)
at
org.apache.uima.adapter.jms.client.BaseUIMAAsynchronousEngineCommon_impl.sendCAS(BaseUIMAAsynchronousEngineCommon_impl.java:759)
I wrote my client as the following. It works as a charm now...
CAS cas = null;
try {
cas = uimaEEEngine.getCAS();
JCas jcas;
try {
jcas = cas.getJCas();
} catch (CASException e) {
throw new ResourceProcessException(e);
}
fillCas(jcas);
uimaEEEngine.sendCAS(cas);
}
catch (Exception e) {
// something wrong happen, release the CAS if you got one
if (cas !=null) {
cas.release();
}
}
I don't know if this should be handled in the asynchronous client or if
it has to be documented. I have the feeling, it could happen to somebody
else. I let you decide...
Thank you very much
Pierre
Le 31/03/2010 17:36, Jaroslaw Cwiklik a écrit :
My bad. Indeed when getCas() is used there is no need to call reset nor
release.
The framework calls release() when the listener callback finishes. I've
created a test program to run the client without a listener and I see no
hang. Here is the complete test program:
import java.util.HashMap;
import java.util.Map;
import org.apache.uima.aae.client.UimaAsynchronousEngine;
import org.apache.uima.adapter.jms.client.BaseUIMAAsynchronousEngine_impl;
import org.apache.uima.cas.CAS;
import org.apache.uima.cas.CASException;
import org.apache.uima.jcas.JCas;
import org.apache.uima.resource.ResourceProcessException;
public class TestUimaASClient {
BaseUIMAAsynchronousEngine_impl uimaAsEngine;
public void initialize() throws Exception {
uimaAsEngine = new BaseUIMAAsynchronousEngine_impl();
Map<String, Object> appCtx = new HashMap<String, Object>();
appCtx.put(UimaAsynchronousEngine.ServerUri, "tcp://localhost:61616");
appCtx.put(UimaAsynchronousEngine.Endpoint, "RoomNumberAnnotatorQueue");
appCtx.put(UimaAsynchronousEngine.CasPoolSize, 1);
appCtx.put(UimaAsynchronousEngine.Timeout, 0);
uimaAsEngine.initialize(appCtx);
}
public void run() throws Exception {
for (int i = 0; i< 150; i++) {
CAS cas = uimaAsEngine.getCAS();
JCas jcas;
try {
System.out.println("UIMA AS Client Sending CAS#" + (i + 1) + "
Request to a Service");
jcas = cas.getJCas();
jcas.setDocumentText("Some Text");
} catch (CASException e) {
throw new ResourceProcessException(e);
}
uimaAsEngine.sendCAS(cas);
}
// done
uimaAsEngine.stop();
}
public static void main(String[] args ) {
TestUimaASClient client = new TestUimaASClient();
try {
client.initialize();
client.run();
} catch( Exception e) {
e.printStackTrace();
}
}
}
The above runs to completion no matter how many CASes are sent.
Pierre, can you test the above client with your service? Just change the
ServerUri and Endpoint settings in the initialize() method.
JC
On Wed, Mar 31, 2010 at 10:53 AM, Eddie Epstein<[email protected]> wrote:
This sounds correct when using sendAndReceiveCAS, but not when
using sendCAS.
With the asynchronous sendCAS interface the application gets the CAS
back within the callback listener registered via addStatusCallbackListener.
And the CAS is *not* supposed to be released in the user's
entityProcessComplete method in the listener class.
Perhaps there is a bug if no listener class is registered?
Eddie
On Wed, Mar 31, 2010 at 9:52 AM, Jaroslaw Cwiklik<[email protected]>
wrote:
You are not calling cas.release() when you are done with the CAS.
Per UIMA AS documentation ("4.2 The UimaAsynchronousEngine Interface -
CAS
getCAS()"
"...CAS getCAS(): Requests a new CAS instance from the CAS pool. This
method
blocks until a free instance of CAS is available in the CAS pool.
Applications that
use getCAS() need to call CAS.reset() before reusing the CAS, or
CAS.release()
to return it to the Cas pool."
The release() places a CAS back into the pool so the subsequent call to
getCAS()
succeeds. An alternate strategy is to have a single CAS instance in the
CAS
pool
call getCAS() to get that instance and enter a while loop. When done
processing
reply, call cas.reset() and do *not* call getCAS() again.
JC
On Tue, Mar 30, 2010 at 5:41 AM, pierre yahoo<[email protected]> wrote:
I'm trying to use UIMA-AS to scale a part of the process of our
application.
I have successfully deployed our process as asynchronous services but I
have tremendous issues with the client.
I'm basically looping synchronously(one at a time) on the following
code.
CAS cas = uimaEEEngine.getCAS();
JCas jcas;
try {
jcas = cas.getJCas();
} catch (CASException e) {
throw new ResourceProcessException(e);
}
fillCas(jcas);
uimaEEEngine.sendCAS(cas);
When I run the application, the client works fine for a while and
suddenly
gets stuck waiting on cas.getJCas()..
I have checked that the asynchronous service have processed all the
previous CAS. The service is still up and running as I can send
requests
from an another client.
When I tracked down who locks the process, I can see that the semaphore
on
CasQueueEntry is not released.
When I looked further, I noticed that the all process is basically lock
when the CasManager_Impl is calling CasPool.getCas(0) . The CasPool is
then
waiting with no timeout for someone to notify it.
I try to change the size of the client CasPool but it didn't really fix
the
issue. Just pushing further the lock...
Does anyone have ever experienced this? Am I doing something wrong ?
Pierre
