In the logfile on tomcat I see very often this message:
We have master/slave configuration for the builders.

Aug 8, 2008 8:09:09 AM org.apache.catalina.core.ApplicationContext log
SEVERE: Error while serving
http://scrat:8080/hudson/view/CWS/job/cwsall-cobertura/lastStableBuild/cobertura/graph
java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedMethodAccessor638.invoke(Unknown Source)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:103)
at org.kohsuke.stapler.Function.bindAndinvoke(Function.java:57)
at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:75)
at
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:440)
at org.kohsuke.stapler.MetaClass$15.dispatch(MetaClass.java:384)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:440)
at org.kohsuke.stapler.MetaClass$7.doDispatch(MetaClass.java:230)
at
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:440)
at org.kohsuke.stapler.MetaClass$9.doDispatch(MetaClass.java:263)
at
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:440)
at org.kohsuke.stapler.MetaClass$9.doDispatch(MetaClass.java:263)
at
org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:30)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:440)
at org.kohsuke.stapler.Stapler.invoke(Stapler.java:361)
at org.kohsuke.stapler.Stapler.service(Stapler.java:121)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:53)
at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:45)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:88)
at
org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at
org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:433)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
at
org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
at
org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at
org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at
org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at
org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Thread.java:619)
Caused by: ClientAbortException: java.net.SocketException: Broken pipe
at
org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:366)
at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:432)
at org.apache.catalina.connector.OutputBuffer.doFlush(OutputBuffer.java:314)
at org.apache.catalina.connector.OutputBuffer.flush(OutputBuffer.java:293)
at
org.apache.catalina.connector.CoyoteOutputStream.flush(CoyoteOutputStream.java:98)
at
javax.imageio.stream.FileCacheImageOutputStream.close(FileCacheImageOutputStream.java:213)
at javax.imageio.ImageIO.write(ImageIO.java:1567)
at hudson.util.ChartUtil.generateGraph(ChartUtil.java:89)
at
hudson.plugins.cobertura.targets.CoverageResult.doGraph(CoverageResult.java:319)
... 44 more
Caused by: java.net.SocketException: Broken pipe
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:92)
at java.net.SocketOutputStream.write(SocketOutputStream.java:136)