We are exploring issue with threads which eventually never ends, use case: when slave configuration has been Saved, tomcat loads for a long time. Is it issue with deadlock, here is the part of the dump which explains:

Handling POST /main_instance/computer/RH_6_mrclin131/configSubmit : http-10080-46" daemon prio=10 tid=0x00007feef4073000 nid=0x7ca5 waiting for monitor entry [0x00007fefa828a000]
13444 java.lang.Thread.State: BLOCKED (on object monitor)
13445 at jenkins.model.Jenkins.save(Jenkins.java:2671)
13446 - waiting to lock <0x0000000701a3e208> (a hudson.model.Hudson)
13447 at hudson.util.PersistedList.onModified(PersistedList.java:173)
at hudson.util.PersistedList.replaceBy(PersistedList.java:85)
13449 at hudson.model.Slave.<init>(Slave.java:164)
13450 at hudson.model.Slave.<init>(Slave.java:140)
13451 at hudson.slaves.DumbSlave.<init>(DumbSlave.java:53)
13452 at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
13453 at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
13454 at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
13455 at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
13456 at org.kohsuke.stapler.RequestImpl.invokeConstructor(RequestImpl.java:447)
13457 at org.kohsuke.stapler.RequestImpl.instantiate(RequestImpl.java:690)
13458 at org.kohsuke.stapler.RequestImpl.access$100(RequestImpl.java:81)
13459 at org.kohsuke.stapler.RequestImpl$TypePair.convertJSON(RequestImpl.java:587)
13460 at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.java:400)
13461 at org.kohsuke.stapler.RequestImpl.bindJSON(RequestImpl.jav