JDK-7084525 : G1: Generate ergonomic decision log records for young gen sizing and for pause prediction
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: gc
  • Affected Version: hs22
  • Priority: P4
  • Status: Closed
  • Resolution: Not an Issue
  • OS: generic
  • CPU: generic
  • Submitted: 2011-08-29
  • Updated: 2022-07-01
  • Resolved: 2022-07-01
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Other
tbdResolved
Related Reports
Relates :  
JDK-7084509 - G1: fix inconsistencies and mistakes in the young list target length calculations
Relates :  
JDK-7088805 - G1: revamp the ergo decision output infrastructure
Relates :  
JDK-7097002 - G1: remove a lot of unused / redundant code from the G1CollectorPolicy class
Relates :  
JDK-7050392 - G1: Introduce flag to generate a log of the G1 ergonomic decisions
Description
This expands 7050392 with ergonomic decision logging for two additional heuristics:

- Young Gen Sizing : why the young gen has the number of regions it has
- Pause Prediction : detailed information on the operation of the pause prediction mechanism
Comments
This has already been done, i.e. -Xlog:gc+ergo* and variants provide a sufficient level of logging; if there is need for further it is better to improve as needed instead of such a generic request. Closing out for now.
01-07-2022
EVALUATION Given that this is an RFE I'm going to just go ahead and retarget it to hs23.
22-09-2011
EVALUATION The information that needs to be logged is all over the place and it's hard to do the changes without some non-trivial amount of restructuring. We already have the basic ergo decision logging in the codebase (done as part of 7050392). I'd like to get this deferred to hs23 please.
21-09-2011
PUBLIC COMMENTS The implementation of this CR will be made easier after the changes for 7084509 (G1: fix inconsistencies and mistakes in the young list target length calculations) have been pushed as they make the decisions taken with regards to pause prediction much easier to follow.
29-08-2011
EVALUATION See Description / Public Comments.
29-08-2011