Hello,

I have recently started using the Amazon EC2 plugin to bring up Jenkins build slaves on demand. They are all created from the same AMI and set to shut down instead of terminate. The transition went very smoothly (as soon as the AMI had everything that was needed) however two of our builds are now misbehaving every single time. I've been able to find some very old slightly similar issues in Jira and Stackoverflow but nothing identical (and nothing using recent version of Jenkins). I am not 100% convinced the EC2 plugin has anything to do with this however this is when the problem started exhibiting.

I've managed to narrow this issue to the 'Clean up unused Subversion modules' option in 'Build environment'. Whenever the build starts (either by SCM poll trigger or manually triggerred), the SCM checkout happens successfully (this is regardless of there being changes) and after the 'At revision xxx' message is printed out in the log, nothing happens anymore (no matter how long the job is left running) apart from the spinning circle. I have discovered that hitting the cancel button when in the console log page (top right next to the progress bar) will display a stacktrace in the build but the build will continue happily afterwards. Here's the stacktrace:

java.lang.InterruptedException
	at java.lang.Object.wait(Native Method)
	at hudson.remoting.Request.call(Request.java:147)
	at hudson.remoting.Channel.call(Channel.java:780)
	at hudson.FilePath.act(FilePath.java:1007)
	at hudson.FilePath.act(FilePath.java:996)
	at hudson.FilePath.isDirectory(FilePath.java:1532)
	at jenkins.plugins.workspace_cleaner.FilePathAdapter.isDirectory(FilePathAdapter.java:52)
	at jenkins.plugins.workspace_cleaner.ModuleCleaner.getSvnModulesIn(ModuleCleaner.java:59)
	at jenkins.plugins.workspace_cleaner.ModuleCleaner.getSvnModulesIn(ModuleCleaner.java:60)
	at jenkins.plugins.workspace_cleaner.ModuleCleaner.getSvnModulesIn(ModuleCleaner.java:60)
	at jenkins.plugins.workspace_cleaner.ModuleCleaner.getSvnModulesInFileSystem(ModuleCleaner.java:43)
	at jenkins.plugins.workspace_cleaner.ModuleCleaner.removeUnconfiguredModules(ModuleCleaner.java:21)
	at jenkins.plugins.workspace_cleaner.JenkinsGlue.setUp(JenkinsGlue.java:32)
	at hudson.maven.MavenModuleSetBuild$MavenModuleSetBuildExecution.doRun(MavenModuleSetBuild.java:655)
	at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:534)
	at hudson.model.Run.execute(Run.java:1720)
	at hudson.maven.MavenModuleSetBuild.run(MavenModuleSetBuild.java:531)
	at hudson.model.ResourceController.execute(ResourceController.java:98)
	at hudson.model.Executor.run(Executor.java:404)

I've worked around this by disabling this option. Let me know if I can provide any more info that could help.