Just updated from 1.377 to 1.381.

Large reporting jobs, where Cobertura output is large (many files around 1MB, totaling 18MB), will have issues while copying "coverage.xml" files from slave machine to main Hudson server.

No error in logs on Slave machine, but we find the following error on the Hudson Server:

Oct 21, 2010 4:40:03 AM hudson.remoting.ProxyOutputStream$Chunk$1 run
WARNING: Failed to write to stream
java.io.IOException: Bad file descriptor
at java.io.FileOutputStream.writeBytes(Native Method)
at java.io.FileOutputStream.write(FileOutputStream.java:247)
at hudson.remoting.ProxyOutputStream$Chunk$1.run(ProxyOutputStream.java:185)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)

The build actually fails then with following stack trace:

Publishing Cobertura coverage report...
Publishing Cobertura coverage results...
FATAL: Unable to parse /home/hudson/hudson/server_installation/jobs/projectname/builds/2010-10-21_03-00-32/coverage35.xml
hudson.util.IOException2: Cannot parse coverage results
at hudson.plugins.cobertura.CoberturaCoverageParser.parse(CoberturaCoverageParser.java:89)
at hudson.plugins.cobertura.CoberturaCoverageParser.parse(CoberturaCoverageParser.java:52)
at hudson.plugins.cobertura.CoberturaPublisher.perform(CoberturaPublisher.java:262)
at hudson.tasks.BuildStepMonitor$3.perform(BuildStepMonitor.java:36)
at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:601)
at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:580)
at hudson.model.AbstractBuild$AbstractRunner.performAllBuildSteps(AbstractBuild.java:558)
at hudson.model.Build$RunnerImpl.post2(Build.java:157)
at hudson.model.AbstractBuild$AbstractRunner.post(AbstractBuild.java:528)
at hudson.model.Run.run(Run.java:1303)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46)
at hudson.model.ResourceController.execute(ResourceController.java:88)
at hudson.model.Executor.run(Executor.java:139)
Caused by: org.xml.sax.SAXParseException: XML document structures must start and end within the same entity.
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:195)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:174)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:388)
at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(XMLScanner.java:1411)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.endEntity(XMLDocumentFragmentScannerImpl.java:902)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.endEntity(XMLDocumentScannerImpl.java:605)
at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.endEntity(XMLEntityManager.java:1393)
at com.sun.org.apache.xerces.internal.impl.XMLEntityScanner.load(XMLEntityScanner.java:1763)
at com.sun.org.apache.xerces.internal.impl.XMLEntityScanner.skipSpaces(XMLEntityScanner.java:1492)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanAttribute(XMLDocumentFragmentScannerImpl.java:1520)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1316)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2747)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:648)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:807)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:737)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:107)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1205)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:522)
at javax.xml.parsers.SAXParser.parse(SAXParser.java:395)
at javax.xml.parsers.SAXParser.parse(SAXParser.java:198)
at hudson.plugins.cobertura.CoberturaCoverageParser.parse(CoberturaCoverageParser.java:81)
... 12 more
Email was triggered for: Failure
Sending email for trigger: Failure
Sending email to: xx@xx.com
Finished: FAILURE

Looking at the file "coverage35.xml" on the Hudson server, we see that the size is 983040 bytes. However, in the slave workspace, this file is 1023819 bytes.

=> As the file size 983040 is a multiple of 64k, and the difference between the original and copied is less than 64k, it is tempting to say that the error must be caused by some buffering issue and/or lack of a output "flush"