RFR (smallish?) 8061611: Remove deprecated command line flags

Jesper Wilhelmsson jesper.wilhelmsson at oracle.com
Mon Nov 24 16:37:13 UTC 2014


Hi Derek,

Yes, any change to a publicly available API requires a CCC.
Let me know if you need any help with the CCC process.
/Jesper

Derek White skrev 24/11/14 17:10:
> Thanks Bengt,
>
> I'll make the spelling change you suggested.
>
> One other question I had is does this require a CCC decision to actually 
> change the command line arguments? Some of the arguments have been discussed 
> in public, so are not truly "internal".
>
> Thanks!
>
>  - Derek
>
> On 11/24/14 6:55 AM, Bengt Rutisson wrote:
>>
>> Hi Derek,
>>
>> Sorry for taking so long to review this.
>>
>> On 2014-11-18 17:40, Derek White wrote:
>>> Hi Team,
>>>
>>> First review request. Please let me know if I've forgotten something or have 
>>> gone completely off the rails.
>>>
>>> The main point of this bug is to remove deprecated -XX options which are 
>>> alias for other options.
>>>
>>> The only complicated part is that one case, /CMSParPromoteBlocksToClaim/ was 
>>> not a true alias for /OldPLABSize/ but a parallel option with different 
>>> defaults that were synchronized in ergo processing. This fix removes the 
>>> /CMSParPromoteBlocksToClaim /variable but preserves using different defaults 
>>> in the CMS case.
>>>
>>> Also in this fix I added warning messages to several remaining undocumented 
>>> command line options aliases. This should ease removal of these options in 
>>> the future
>>> CMSMarkStackSize ==> MarkStackSize        (MarkStackSize not documented either, but came in jdk6)
>>> G1MarkStackSize  ==> MarkStackSize
>>> CMSMarkStackSizeMax ==> MarkStackSizeMax  (MarkStackSizeMax not documented either)
>>> ParallelMarkingThreads =>  ConcGCThreads  (ConcGCThreads came in jdk6)
>>> ParallelCMSThreads     ==> ConcGCThread
>>>
>>> Thanks,
>>>  - Derek
>>>
>>> *Webrev*: http://cr.openjdk.java.net/~drwhite/8061611/webrev.00/
>>>
>>> *Bug*: https://bugs.openjdk.java.net/browse/JDK-8061611
>>
>> Looks good to me. One minor nit regarding the naming of the new constants 
>> that you introduce:
>>
>>  682   static const int defaultDynamicOldPLABSize = 16;
>>  683   static const int defaultStaticOldPLABSize  = 50;
>>
>> HotSpot does not have a common guideline for how to name constants. There are 
>> at least three widely used naming standards:
>>
>> - All caps: DEFAULT_DYNAMIC_OLD_PLAB_SIZE
>> - Like an instance variable: _default_dynamic_old_plab_size
>> - Like a flag: DefaultDynamicOldPLABSize
>>
>> I think it is hard to say which one is "standard" but I would prefer if we 
>> don't introduce yet another naming standard for constants. Do you mind 
>> changing to one of these? Personally I prefer the last one (the "Like a flag" 
>> version).
>>
>> Bengt
>>
>>>
>>> *Testing*:
>>> jprt:
>>>     Saw 1-2 intermittent failures that went away on retesting - hangs and 
>>> timeouts.
>>>
>>> refworkload:
>>>     no differences
>>>
>>> jtreg: Saw a few unexplained results. Not sure if typical or not:
>>>
>>>
>>>             Execution failed: `main' threw exception: java.lang.Exception:
>>>             jmap -heap exited with error code: 1
>>>
>>>       * gc/metaspace/CompressedClassSpaceSizeInJmapHeap.java
>>>         <http://oklahoma.us.oracle.com/net/bussund0416//export/users/drwhite/hs-gc-mine/hotspot/test/JTwork/gc/metaspace/CompressedClassSpaceSizeInJmapHeap.jtr>:
>>>         Checks that jmap -heap contains the flag CompressedClassSpaceSize
>>>
>>>
>>>             Program
>>>             `/export/users/drwhite/test-builds/j2sdk-image.11.17.2014/bin/java'
>>>             interrupted! (timed out?)
>>>
>>>       * closed/runtime/AppCDS/SharedArchiveConsistency.java
>>>         <http://oklahoma.us.oracle.com/net/bussund0416//export/users/drwhite/hs-gc-mine/hotspot/test/JTwork/closed/runtime/AppCDS/SharedArchiveConsistency.jtr>:
>>>         SharedArchiveConsistency
>>>
>>>     Plus a bunch of tests that are labelled "ignored".
>>>
>>>
>>
>

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