JEP 228: Add More Diagnostic Commands
| Owner | Staffan Larsen |
| Type | Feature |
| Scope | Implementation |
| Status | Closed / Delivered |
| Release | 9 |
| Component | hotspot / svc |
| Discussion | serviceability dash dev at openjdk dot java dot net |
| Effort | S |
| Duration | M |
| Relates to | JEP 279: Improve Test-Failure Troubleshooting |
| Reviewed by | Mikael Vidstedt |
| Endorsed by | Mikael Vidstedt |
| Created | 2014/05/22 13:55 |
| Updated | 2017/03/07 11:28 |
| Issue | 8043764 |
Summary
Define additional diagnostic commands, in order to improve the diagnosability of Hotspot and the JDK.
Description
This is a list of the new commands (exact names are TBD):
print_class_summary
- Print a list of all loaded classes and their inheritence structure.
- Responsible group: runtime
print_codegenlist
- Print methods queued for compilation with either C1 or C2 (separate queues)
- Responsible group: compiler
print_utf8pool
- Print all UTF-8 string constants.
- Responsible group: runtime
datadump_request
- Signal the JVM to do a data-dump request for JVMTI.
- Responsible group: serviceability
dump_codelist
- Print n-methods (compiled) with full signature, address range, and state (alive, nonentrant, and zombie).
- Allow selection of printing to stdout or to a file.
- Allow XML or text printout.
- Responsible group: compiler
print_codeblocks
- Print the size of the code cache and a list of blocks in the code cache, with adresses.
- Responsible group: compiler
set_vmflag
- Set a command-line flag/option in VM or the libraries.
- Responsible group: servicability
Testing
There needs to be a test for each command to verify the output.