JDK-8186091 : Optimize OopMapCache lookup
  • Type: CSR
  • Component: hotspot
  • Sub-Component: runtime
  • Priority: P3
  • Status: Closed
  • Resolution: Approved
  • Fix Versions: 10
  • Submitted: 2017-08-10
  • Updated: 2017-08-17
  • Resolved: 2017-08-16
Related Reports
CSR :  
JDK-8186042 - Optimize OopMapCache lookup
Description
Summary
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Remove the Hotspot option -XX:+TraceOopMapGeneration and replace the information with -Xlog:interpreter+oopmap={debug,trace}.

Problem
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This option has only been used in non-product mode to historically debug the interpreter oopmap generation which happens during GC safepoint.   I've changed it to use our modern logging facility so that I can write tests for the optimization that I'm working on.

Solution
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Since the option -XX:+TraceOopMapGeneration has only been a develop flag and not a product flag, we have agreed in previous instances that this can be removed without deprecation.   The same output will come out with logging.

Specification
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I was planning to do this in conjunction with the OopMapCache optimization.

open webrev at http://cr.openjdk.java.net/~coleenp/8186042.01/webrev
Comments
Setting a few additional fields and moving the request to approved.
16-08-2017
Yes, we made this decision about develop flag removal when we were doing logging. We debated the need for CCC at the time and decided to write a CCC for the flags we were removing. Thanks.
14-08-2017
I agree that this rarely used develop flag can be removed rather than going through the deprecation process.
14-08-2017