Request for reviews (S): 6914622: Print values of all flags for product VM

Y. Srinivas Ramakrishna Y.S.Ramakrishna at Sun.COM
Wed Jan 6 14:55:21 PST 2010

On 01/06/10 14:44, Vladimir Kozlov wrote:
> Y. Srinivas Ramakrishna wrote:
>> Hi Vladimir --
>> The following are suggestions/questions: (I do not have
>> strong views on what you choose to do, and am fine with whatever
>> you decide).
>> (1) For PrintFlagsInitial, i would in the documentation string
>>     in globals,hpp, add that it also exits the vm after printing
>>     (if you choose to retain the exiting behaviour, see below).
> Done.
> Yes, I want to keep the exiting behavior.
> The initial flags values are meaningless before argument parsing
> and ergonomics. The main purpose of this flag, as I understand,
> is to list all available flags and to verify correctness of initial values.
> You can also use it to compare with PrintFlagsFinal output
> to see how ergonomic works.


>>     Anyone know why we might want to exit the VM after printing the
>>     flags? (i.e. the history of -Xprintflags which you have mimiced 
>> here.)
>>     Is there a particular use case this kind of print-and-exit 
>> functionality
>>     is targeted at?
>> (2) I would personally be inclined to delete Xprintflags since it's
>>     not a product flag and can therefore, it seems to me, be deleted
>>     without approval.  Why have duplicate functionality/interfaces
>>     even if the duplication is only in debug mode.
> I doubt we can do it now since you can google it :).

Does that apply to even flags that are not exposed in the product build?

Besides, that would mean that _any_ flag change would need approval
because with open source you can google (or bing :) all the code
and of course this email (on the openjdk list) which contains that string :-)

-- ramki

> Thanks,
> Vladimir
>> Otherwise looks good.
>> -- ramki
>> On 01/06/10 14:13, Vladimir Kozlov wrote:
>>> Fixed 6914622: Print values of all flags for product VM
>>> Change the flag -XX:+PrintFlagsFinal to product.
>>> Add new product flag -XX:+PrintFlagsInitial to print all VM flags before
>>> arguments processing, it is duplicate of debug flag -Xprintflags.
>>> Move all related print flags together.
>>> Partially contributed by: Gary Benson
>>> Note, the changes are different from suggested by Gary Benson
>>> since I can't change -Xprintflags without approval, so I added
>>> new option instead.
>>> Reviewed by:
>>> Fix verified (y/n): y
>>> Other testing:
>>> JPRT

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