Jenkins error: java.io.FileNotFoundException: ... (Too many open files)

Jenkins needs restart? Building remotely on ovirt-srv21.phx.ovirt.org <http://jenkins.ovirt.org/computer/ovirt-srv21.phx.ovirt.org> (fc24 phx integ-tests physical) in workspace /home/jenkins/workspace/ovirt-system-tests_manual java.io.FileNotFoundException: /var/lib/data/jenkins/jobs/ovirt-system-tests_manual/builds/856/changelog.xml (Too many open files) at java.io.FileOutputStream.open0(Native Method) at java.io.FileOutputStream.open(FileOutputStream.java:270) at java.io.FileOutputStream.<init>(FileOutputStream.java:213) at java.io.FileOutputStream.<init>(FileOutputStream.java:162) at org.jenkinsci.plugins.multiplescms.MultiSCM.checkout(MultiSCM.java:119) at hudson.scm.SCM.checkout(SCM.java:495) at hudson.model.AbstractProject.checkout(AbstractProject.java:1276) at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:560) at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86) at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:485) at hudson.model.Run.execute(Run.java:1735) at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43) at hudson.model.ResourceController.execute(ResourceController.java:97) at hudson.model.Executor.run(Executor.java:405) ERROR: Step ?Post build task? aborted due to exception: