Hi,
As the Serviceability Agent has been _the_ new and interesting way to
find things post-mortem in the JVM [1], I'd like to propose an update
which continues that tradition.
8010278 SA: provide mechanism for using an alternative SA debugger
back-end.
https://jbs.oracle.com/bugs/browse/JDK-8010278
http://cr.openjdk.java.net/~kevinw/8010278/webrev.00/
This is about making the SA more flexible, so we aren't tied to the
given native libraries to open cores/memory dumps. Given this change, a
3rd party debugger or tool can interact freely with the SA tools
(StackTrace, ObjectHistogram, etc...) and provide its own backend
implementation to actually open a core/memory dump.
Primarily for platform-independent core file debugging. If you ever had
to open a "foreign" core, find the right hardware, etc... this is
relevant. I'm thinking of https://java.net/projects/kjdb which can
serve as a proof of concept.
The changes are:
The main redirection is in HotSpotAgent.java, where we respect a
property (i.e. -Dsa.altHotSpotAgent=...) to name an alternate debugger.
Remove calls to System.exit.
Tool classes (and CLHSDB) should have a constructor that takes a
JVMDebugger, to remove the assumption that a Tool's JVM will only ever
contain one debugee. It doesn't address that VM is a singleton and if a
tool opens multiple sessions then they would need to be from the same
JVM version.
Thanks
Kevin
[1] If you weren't in a circa 1.4.2 demo of the SA when all you had
previously was a few fragile dbx macros, that got you a few very
specific details, the night vs. day comparison of no SA vs. SA could be
missed. 8-)
