We use workspace with large number of files, since the last update of the Jenkins Disk Usage plugin our build post processing is taking ages (4 times slower). We notice the slowdown only on OSX slaves.

We suspect this feature in the plugin : Don't follow symlinks

Here the thread dump when the job completed but the slave is still busy with the plugin :

"pool-1-thread-101 for channel" Id=128 Group=main BLOCKED on hudson.remoting.RemoteClassLoader@fda5bfa owned by "pool-1-thread-767 for channel" Id=2764
at java.lang.ClassLoader.loadClass(ClassLoader.java:291)

• blocked on hudson.remoting.RemoteClassLoader@fda5bfa
  at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
  at hudson.plugins.disk_usage.DiskUsageUtil.isSymlink(DiskUsageUtil.java:175)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil.getFileSize(DiskUsageUtil.java:201)
  at hudson.plugins.disk_usage.DiskUsageUtil$DiskUsageCallable.call(DiskUsageUtil.java:399)
  at hudson.plugins.disk_usage.DiskUsageUtil$DiskUsageCallable.call(DiskUsageUtil.java:380)
  at hudson.remoting.UserRequest.perform(UserRequest.java:118)
  at hudson.remoting.UserRequest.perform(UserRequest.java:48)
  at hudson.remoting.Request$2.run(Request.java:328)
  at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
  at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
  at java.util.concurrent.FutureTask.run(FutureTask.java:138)
  at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
  at java.lang.Thread.run(Thread.java:695)

Number of locked synchronizers = 1

• java.util.concurrent.locks.ReentrantLock$NonfairSync@65962a71

Downgrading the plugin to 0.20 fixed our problem