Using jmap on Ubuntu Mate 18.04-64bits with Oracle JDK 10.0.1-64bits, the tool works only when running both the target and the tool as root, but using the same normal user for running both gives the following error:
`Exception in thread "main" com.sun.tools.attach.AttachNotSupportedException: Unable to open socket file /proc/13538/cwd/.attach_pid13538: target process 13538 doesn't respond within 10500ms or HotSpot VM not loaded at jdk.attach/sun.tools.attach.VirtualMachineImpl.<init>(VirtualMachineImpl.java:103) at jdk.attach/sun.tools.attach.AttachProviderImpl.attachVirtualMachine(AttachProviderImpl.java:58) at jdk.attach/com.sun.tools.attach.VirtualMachine.attach(VirtualMachine.java:207) at jdk.jcmd/sun.tools.jmap.JMap.executeCommandForPid(JMap.java:124) at jdk.jcmd/sun.tools.jmap.JMap.main(JMap.java:114)`
When using root user to run the following command jmap -clstats <pid>, everything works fine but I found some difficulties to understand the meaning of the output columns:
Is there any official documentation that explains the meaning of each column ?