RFR 8134995(M): [REDO] GC: implement ranges (optionally constraints) for those flags that have them missing

sangheon.kim sangheon.kim at oracle.com
Fri Sep 11 00:01:18 UTC 2015

Hi all,

Please review this patch for command-line validation for GC flags.
This REDO patch is adding ranges and implementing constraint functions 
for GC flags.

Original CR of JDK-8078555 was backout as it made a test failure from 
And also there were some discussion of OOM handling.

Most parts are same as JDK-8078555 except below:
1. Changed 'range' for some flags.
2. Excluded 3 flags for TestOptionsWithRanges.java test. These flags 
make this test unstable as it tries to allocate huge amount of memory.

And below are the suggestion note for JDK-8078555:
1. Exponential notation for 'double' type variable parse: Previously 
there were some discussion for maximum value for double type flags from 
code review of JDK-8059557 and JDK-8112746. And Kim and I decided not to 
add upper limit unless there are problems with DBL_MAX. And as 255 is 
the maximum length that can be passed via command-line, we introduced 
exponential notation to avoid this limit. ( arguments.cpp )
2. These GC flags ranges are not ideal ranges but ranges which don't 
make problem with current source code.
     If one flag makes some problem but hard to find good range, I added 
some ranges.
3. There are some constraint functions to avoid overflow.
4. Test applications are changed: as some of them assumed to be 
ParallelGC or to check it's output messages.
5. Includes cleanup of JDK-8133565: GC -2nd followup to JDK-8059557.



JPRT, UTE(vm.quick-pcl) and 


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