We have also found out that the actual limiting number is the number of xUnit steps executed. For example, if the job has two xUnit post-build steps, then the 10th build gets stuck. Same with four xUnit steps per build. In each case, it is the 20th xUnit step that freezes.

Further test cases have resolved that the limiting factor is, in fact, dependent on number of testcase files and the number of runs. The size of the files or the number of testcases within the files do not seem to matter.

To be precise, when we have 0 or 1 file in the result set, the number of runs follows this equation:

runs * (1.38 + number of files) = 338.

When we have 2 or more files, the numbers are somewhat different:

runs * (1.33 + number of files) = 790.

Old issue, please refile if broken.

We have exactly this isse here frequently with jobs having a large number of testcases.
What else information is needed to fix this problem ?

Hereafter the job that got stuck at 16.01 10:47:23.
Today morning i pressed the stop button at 8:24, and you see the

16.01 10:47:22 </ul>
16.01 10:47:23 [xUnit] [INFO] - Starting to record.
16.01 10:47:23 [xUnit] [INFO] - Processing BoostTest-1.x (default)
16.01 10:47:23 [xUnit] [INFO] - [BoostTest-1.x (default)] - 2 test report file(s) were found with the pattern '*.xml' relative to '/home/alcatel/workspace/R8Light' for the testing framework 'BoostTest-1.x (default)'.
18.01 08:24:25 [xUnit] [WARNING] - Caught exception of unexpected type class java.lang.InterruptedException, rethrowing
18.01 08:24:25 ERROR: Step ‘Publish xUnit test result report’ aborted due to exception:
18.01 08:24:25 java.lang.InterruptedException
18.01 08:24:25 at java.lang.Object.wait(Native Method)
18.01 08:24:25 at hudson.remoting.Request.call(Request.java:147)
18.01 08:24:25 at hudson.remoting.Channel.call(Channel.java:780)
18.01 08:24:25 at hudson.FilePath.act(FilePath.java:979)
18.01 08:24:25 at hudson.FilePath.act(FilePath.java:968)
18.01 08:24:25 at org.jenkinsci.plugins.xunit.XUnitProcessor.performTests(XUnitProcessor.java:138)
18.01 08:24:25 at org.jenkinsci.plugins.xunit.XUnitProcessor.performXUnit(XUnitProcessor.java:81)
18.01 08:24:25 at org.jenkinsci.plugins.xunit.XUnitPublisher.perform(XUnitPublisher.java:112)
18.01 08:24:25 at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
18.01 08:24:25 at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:782)
18.01 08:24:25 at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:723)
18.01 08:24:25 at hudson.model.Build$BuildExecution.post2(Build.java:185)
18.01 08:24:25 at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:668)
18.01 08:24:25 at hudson.model.Run.execute(Run.java:1763)
18.01 08:24:25 at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
18.01 08:24:25 at hudson.model.ResourceController.execute(ResourceController.java:98)
18.01 08:24:25 at hudson.model.Executor.run(Executor.java:410)
18.01 08:24:25 [PostBuildScript] - Execution post build scripts.
18.01 08:24:25 [R8Light] $ /bin/bash -xe /tmp/hudson4109735917483500943.sh

Hi Gregory, can you help me here ?
Thanks in advance, Eckhard !

Here i added the full Java trace from core dump of the hanging Jenkins Jobs.

Jenkins version 1.6.43
xUnit version 1.99

java version "1.7.0_91"
OpenJDK Runtime Environment (IcedTea 2.6.3) (7u91-2.6.3-0ubuntu0.14.04.1)
OpenJDK 64-Bit Server VM (build 24.91-b01, mixed mode)
Linux slave 4.2.0-19-lowlatency #23~14.04.1-Ubuntu SMP PREEMPT Thu Nov 12 13:19:01 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

Here a thread where Java threads also were hanging at "java.util.zip.ZipFile.getEntry":
https://github.com/aws/aws-sdk-java/issues/238
same as we observe here. They also found a solution, IMHO:
"And yes, using this system property gets rid of the thread blocks :+1: Thank you so much for the suggestion!"

Does not appear to be an ec2 plugin issue.

Yes, we do not have ec2 plugin in use, i can confirm that.
And we decided to try an upgrade of Java version now, using oracle 1.8.0_66-b17 since last week,
Since we did that, there was no hanging, but time is too short to say something, not many test were running since snowzilla hit eastcost.

Propose to switch Subject, to "Build is hanging in xUnit plugin processing"

Please try with lastest version of Jenkins and the plugin, i could not reproduce this scenario also if detailed with thread dump.