Hello,
We're querying a webservice using a 'ThreadSafeClientConnManager'.
Platform: windows 2003 Server 64bit
httpClient 4.0
jre 6 update 13 on Tomcat 6.0.18
We're setting a global response timeout with:
HttpParams objHttpParams = new BasicHttpParams();
HttpProtocolParams.setVersion(objHttpParams, HttpVersion.HTTP_1_1);
HttpConnectionParams.setSoTimeout(objHttpParams, responseTimeout);
ClientConnectionManager cm = new ThreadSafeClientConnManager(objHttpParams,
HttpUtils.createDefaultSchemeRegistry());
this.objHttp = new DefaultHttpClient(cm, objHttpParams);
For every webservice call, if the response timeout (at call level) is
greater than 0 then:
if (objCall.responseTimeout != 0)
objPost.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT,
objCall.responseTimeout);
Then we send the request:
StringEntity entity = new StringEntity(request.createRequestParameters());
entity.setContentType(request.contentType);
objPost.setEntity(entity);
return (this.objHttp.execute(objPost));
And we read the response:
bis = new BufferedInputStream(entity.getContent());
ByteArrayOutputStream buffer = new ByteArrayOutputStream(httpOutBufferSize);
byte[] tmp = new byte[httpOutBufferSize];
int numBytesRead = 0;
while ((numBytesRead = bis.read(tmp)) >= 0) buffer.write(tmp, 0,
numBytesRead);
bis.close();
bis = null;
Performing a thread dump, we can see many threads blocked waiting a response
several minutes (2,3,4 minutes) when the maximum response timeout is 60
seconds (at webservice and call level).
This is the dump of one of these threads:
Name: http-80-795
State: RUNNABLE
Total blocked: 3.603 Total waited: 3.127
Stack trace:
java.net.SocketInputStream.socketRead0(Native Method)
java.net.SocketInputStream.read(Unknown Source)
org.apache.http.impl.io.AbstractSessionInputBuffer.fillBuffer(AbstractSessio
nInputBuffer.java:130)
org.apache.http.impl.io.SocketInputBuffer.fillBuffer(SocketInputBuffer.java:
127)
org.apache.http.impl.io.AbstractSessionInputBuffer.readLine(AbstractSessionI
nputBuffer.java:233)
org.apache.http.impl.conn.DefaultResponseParser.parseHead(DefaultResponsePar
ser.java:98)
org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.ja
va:210)
org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(Abst
ractHttpClientConnection.java:271)
org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(Defa
ultClientConnection.java:227)
org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader(Ab
stractClientConnAdapter.java:229)
org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestEx
ecutor.java:292)
org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.jav
a:126)
org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDir
ector.java:447)
org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.ja
va:641)
org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.ja
va:576)
org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.ja
va:554)
com.vpfw.proxy.services.C.C.A(Unknown Source)
com.vpfw.proxy.services.C.C.A(Unknown Source)
com.vpfw.proxy.services.C.C.A(Unknown Source)
com.vpfw.proxy.servlet.E.A(Unknown Source)
com.vpfw.proxy.servlet.G.service(Unknown Source)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(Application
FilterChain.java:290)
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterCh
ain.java:206)
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.ja
va:233)
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.ja
va:191)
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128
)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102
)
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java
:109)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http
11Protocol.java:583)
org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
java.lang.Thread.run(Unknown Source)
The pool seems to work well, the connections are obtained and returned to
the pool correctly.
Could anybody help me to understand what's going on? If a http dump is
needed, I'll try to do it (it's a production environment with an average of
500 http simultaneous requests to the webservices).
Thanks in advance,
Joan.
