RFR: JDK-8318636: Add jcmd to print annotated process memory map

[Chris Plummer]

On Sun, 22 Oct 2023 10:08:49 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

> Analysts and supporters often use /proc/xx/maps to make sense of the memory footprint of a process.
> 
> Interpreting the memory map correctly can help when used as a complement to other tools (e.g. NMT). There even exist tools out there that attempt to annotate the process memory map with JVM information.
> 
> That, however, can be more accurately done from within the JVM, at least for mappings originating from hotspot. After all, we can correlate the mapping information in NMT with the VMA map.
> 
> Example output:
> 
> [example.system.map.txt](https://github.com/openjdk/jdk/files/13062903/example.system.map.txt)
> 
> This patch adds the VM annotations for VMAs that are *mmaped*. I also have an experimental patch that works with malloc'ed memory, but it is not ready yet for consumption and I leave that part of for now.

The hs_err file includes a dump of the maps file. It seems these annotations would be useful there also.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/16301#issuecomment-1774300905