[JIRA] (JENKINS-61792) DoubleLaunchChecker false positive

[wadex.cl...@intel.com (JIRA)]

Title: Message Title

Wade Cline created an issue   Jenkins / JENKINS-61792 DoubleLaunchChecker false positive Issue Type: Bug Assignee: Unassigned Components: core Created: 2020-04-02 23:41 Environment: Debian GNU/Linux 10 openjdk 11.0.6 2020-01-14 OpenJDK Runtime Environment (build 11.0.6+10-post-Debian-1deb10u1) OpenJDK 64-Bit Server VM (build 11.0.6+10-post-Debian-1deb10u1, mixed mode, sharing) Jenkins ver. 2.204.5 Launched & installed via standard Debian service Accessed directly Priority: Minor Reporter: Wade Cline (Copied from e-mail) A few weeks ago we ran into an issue where Jenkins reported that two instances were running with the same host directory: -------- Error Jenkins detected that you appear to be running more than one instance of Jenkins that share the same home directory '/var/lib/jenkins'. This greatly confuses Jenkins and you will likely experience strange behaviors, so please correct the situation. This Jenkins:1541674003 contextPath="" at 29119@NPG-CID-Jenkins-OR Other Jenkins:1541674003 contextPath="" at 29119@NPG-CID-Jenkins-OR -------- The two identifiers reported were exactly the same. Looking at the source, I found 'core/src/main/java/hudson/util/DoubleLaunchChecher.java', and, from there, found the following entry in the Jenkins log file: -------- 2020-03-17 01:14:10.096+0000 [id=66] SEVERE hudson.util.DoubleLaunchChecker#execute: Collision detected. timestamp=1584403930000, expected=1584403930092 -------- Note that the time stamps are a mere 92 milliseconds apart and appear to be from the same instance. At first I expected that this might be a filesystem timestamp resolution issue, but running 'ls -a --full-time' showed that the filesystem did indeed support high-resolution timestamps (output snipped): -------- rw-rr- 1 jenkins jenkins 53 2020-03-20 11:50:10.193592799 -0700 .owner -------- I also wrote a quick Java test program to see if the timestamping code worked as expected, and it did indeed: -------- import org.apache.commons.io.FileUtils; import java.io.File; import java.io.IOException; public class Test { public static void main(String args[]) { File timestampFile = new File(".owner"); long t = timestampFile.lastModified(); try { FileUtils.writeStringToFile(timestampFile, "Oh God how did this get here I am not good with computer"); } catch (IOException e) { System.out.println("It broke"); } long t2 = timestampFile.lastModified(); System.out.println("Old Timestamp: " + t); System.out.println("New Timestamp: " + t2); } } -------- root@NPG-CID-Jenkins-OR:~# java -cp "/root/jenkins/WEB-INF/lib/" ./Test.java Note: ./Test.java uses or overrides a deprecated API. Note: Recompile with -Xlint:deprecation for details. Old Timestamp: 1584733878748 New Timestamp: 1584734059361 root@NPG-CID-Jenkins-OR:~# java -cp "/root/jenkins/WEB-INF/lib/" ./Test.java Note: ./Test.java uses or overrides a deprecated API. Note: Recompile with -Xlint:deprecation for details. Old Timestamp: 1584734059361 New Timestamp: 1584734060529 root@NPG-CID-Jenkins-OR:~# java -cp "/root/jenkins/WEB-INF/lib/" ./Test.java Note: ./Test.java uses or overrides a deprecated API. Note: Recompile with -Xlint:deprecation for details. Old Timestamp: 1584734060529 New Timestamp: 1584734062861 -------- So now I suspect that perhaps the DoubleLaunchChecker is erroneously being run twice on startup, but am not sure how I would test that hypothesis. Has anyone seen this issue before, or have any ideas how to debug it? Since the issue appears to be a false positive we've gone ahead and told Jenkins to ignore the issue for now. Add Comment   This message was sent by Atlassian Jira (v7.13.12#713012-sha1:6e07c38) -- You received this message because you are subscribed to the Google Groups "Jenkins Issues" group. To unsubscribe from this group and stop receiving emails from it, send an email to jenkinsci-issues+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/jenkinsci-issues/JIRA.205632.1585870918000.5537.1585870920097%40Atlassian.JIRA.