URGENT: Request for review: 7122222: GC log is limited to 2G for 32-bit

[Tao Mao]

Thank you for looking at it, Yumin.

Please see inline.

Tao

On 6/4/13 4:14 PM, Yumin Qi wrote:
> Hi, Tao
>
>   The change works only when LP64 is not defined as "1", I would think 
> you need to check if it is defined instead. (how about LP64=other?, 
> source code only check if it is defined).
Is that true?

I found the following exist in the current make files.

make//bsd/makefiles/defs.make:34:ifeq ($(LP64), 1)
make//linux/makefiles/defs.make:40:ifeq ($(LP64), 1)
make//solaris/makefiles/defs.make:33:ifeq ($(LP64), 1)

ifeq ($(LP64), 1)
   ARCH_DATA_MODEL ?= 64
else
   ARCH_DATA_MODEL ?= 32
endif


It looks that it assumes users should set LP64=1 in order to get a 
correct build.

Just presenting something I found. I'm not sure about this, either. The 
make files are a mystery to me.

>   I am not a reviewer.
>
> Thanks
> Yumin
>
> On 6/4/2013 4:03 PM, Tao Mao wrote:
>> Since the changeset touched makefiles, I've included 
>> build-dev at openjdk.java.net .
>>
>> I need to push the hsx24 bug asap. Please review it.
>>
>> Thanks.
>> Tao
>>
>> On 6/4/13 2:37 PM, Tao Mao wrote:
>>> Hi all,
>>>
>>> Need reviews to catch RDP2.
>>>
>>> The current webrev is a working solution to all platforms, Linux, 
>>> Windows, and Solaris.
>>> http://cr.openjdk.java.net/~tamao/7122222/webrev.00/
>>>
>>> Thanks.
>>> Tao
>>>
>>> On 5/30/13 10:21 AM, Tao Mao wrote:
>>>> Included runtime dev to see whether they have some idea to handle 
>>>> the compilation choices.
>>>>
>>>> For now, it's been verified that the fix is functionally sufficient.
>>>>
>>>> Thanks.
>>>> Tao
>>>>
>>>> On 5/29/13 5:27 PM, Tao Mao wrote:
>>>>> Thank you, Mikael.
>>>>>
>>>>> Please see inline.
>>>>>
>>>>> Reviewers, please review it based on the following new observation.
>>>>>
>>>>> Tao
>>>>>
>>>>> On 5/27/13 2:05 AM, Mikael Gerdin wrote:
>>>>>> Tao,
>>>>>>
>>>>>> On 2013-05-25 02:19, Tao Mao wrote:
>>>>>>> 7ux bug
>>>>>>>
>>>>>>> webrev:
>>>>>>> http://cr.openjdk.java.net/~tamao/7122222/webrev.00/
>>>>>>>
>>>>>>> changeset:
>>>>>>> (1) make -D_FILE_OFFSET_BITS=64 only available to generating 
>>>>>>> ostream.o
>>>>>>>
>>>>>>> Why conservative rather than making -D_FILE_OFFSET_BITS=64 globally
>>>>>>> applicable?
>>>>>>>
>>>>>>> Global setting of -D_FILE_OFFSET_BITS=64 on linux works fine; 
>>>>>>> however,
>>>>>>> there are at least five code conflicts if introducing the flag 
>>>>>>> globally
>>>>>>> to Solaris.
>>>>>>>
>>>>>>> One was resolved as in os_solaris.inline.hpp, but the rest four 
>>>>>>> files
>>>>>>> had conflicts deep in c library. Even if they are excluded from 
>>>>>>> setting
>>>>>>> -D_FILE_OFFSET_BITS=64, the compiled VM is corrupted.
>>>>>>>
>>>>>>> (2) For now, no Windows solution.
>>>>>>> I haven't found any clean solution for solving this problem on 
>>>>>>> Windows.
>>>>>>
>>>>>> This seems like an insufficient fix if you can't make it work on 
>>>>>> all platforms. I tried building with "-D_LARGEFILE64_SOURCE 
>>>>>> -D_FILE_OFFSET_BITS=64" ons Solaris and hit an #error in libelf.h 
>>>>>> saying it wasn't supported so I understand your problem there.
>>>>> Yes, that's my grief :( you touched them, a bunch of them. That's 
>>>>> why I chose to apply the flag only to the files (ostream.cpp and 
>>>>> ostream.hpp) I want the effect.
>>>>>>
>>>>>> Instead I suggest that you use the compatibility API described in 
>>>>>> lf64(5) on Solaris. This API consists of fopen64, ftell64 and 
>>>>>> friends and is exposed when "-D_LARGEFILE64_SOURCE" is set.
>>>>>>
>>>>>> The same "-D_LARGEFILE64_SOURCE" is available on Linux and has 
>>>>>> the added advantage of not changing any existing symbols and 
>>>>>> therefore we can set the define for all files instead of just 
>>>>>> ostream
>>>>>>
>>>>>> This approach has the added advantage that it more closely 
>>>>>> resembles the changes which will be needed for Windows anyway. 
>>>>>> Those changes would consist of changing calls to ftell/fseek to 
>>>>>> 64-bit versions and changing fopen to fopen64 on Solaris/Linux.
>>>>> Both ways have pros and cons. The current implementation excludes 
>>>>> the usage of fopen64, providing portability (since there's no 
>>>>> fopen64 for Windows). Meanwhile, I understand your suggestion 
>>>>> provides other benefits.
>>>>>
>>>>> This Sun White Paper 
>>>>> (http://unix.business.utah.edu/doc/os/solaris/misc/largefiles.pdf) 
>>>>> summarizes the usage of the flags on solaris (Page 5-26). And, it 
>>>>> should apply to Linux the same way as was agreed across platforms.
>>>>>
>>>>>>
>>>>>> Since there is no fopen64 on Windows it seems that the default 
>>>>>> fopen already supports large files.
>>>>> I tested, and you are correct that the 32-bit VM on Windows can 
>>>>> write beyond 2GB (and beyond 4GB). Thank you, it's solved "half of 
>>>>> my problem" :)
>>>>>>
>>>>>> /Mikael
>>>>>>
>>>>>>>
>>>>>>> test:
>>>>>>> (1) Ability to write over 2g file for 32-bit builds were 
>>>>>>> verified on the
>>>>>>> following configurations.
>>>>>>>
>>>>>>> Linux * i586
>>>>>>> Solaris * i586
>>>>>>> Solaris * sparc
>>>>>>>
>>>>>>> (2) Need a JPRT test for sanity check.
>>>>>>
>