RFR(XS): 8065050: vm crashes during CDS dump when very small SharedMiscDataSize is specified

[Calvin Cheung]

Hi David,

On 12/4/2014 3:14 PM, David Holmes wrote:
> On 4/12/2014 11:40 AM, Calvin Cheung wrote:
>> Hi Jiangli,
>>
>> I've updated the webrev at the same location:
>>      http://cr.openjdk.java.net/~ccheung/8065050/webrev/
>
> Seems okay. Do we have a test that sets the flags to these allowed 
> minimum values and dumps and then uses the archive?

I've added more test scenarios to the testcase.
Updated webrev is at the same location.

thanks,
Calvin


>
> Thanks,
> David
>
>> Previous version is saved at:
>>      http://cr.openjdk.java.net/~ccheung/8065050/webrev.00/
>>
>> thanks,
>> Calvin
>>
>> On 12/3/2014 3:53 PM, Jiangli Zhou wrote:
>>> Hi Calvin,
>>>
>>> On 12/03/2014 03:51 PM, Calvin Cheung wrote:
>>>> On 12/3/2014 2:55 PM, Jiangli Zhou wrote:
>>>>> Hi Calvin,
>>>>>
>>>>> It's better to define 12M and 16M as enums in metaspaceShared.hpp
>>>>> now they are referenced in more than one place.
>>>> So global.hpp will need to include metaspaceShared.hpp.
>>>>>
>>>>> I also have some questions. The 12M/16M are not introduced by this
>>>>> change, do you know why those values were chosen as the default RO
>>>>> and RW sizes?
>>>> Sorry. I don't know the reasons why those values were chosen.
>>>>> Now we require both spaces have to be at lease 12M on 32-bit
>>>>> machines and 16M on 64-bit machine, is it a reasonable requirement?
>>>>> What's the minimum size requirement for the RO and RW spaces with
>>>>> the default classlist?
>>>>
>>>> Below are the numbers for the RO and RW spaces with the default
>>>> classlist for various platforms:
>>>> =====
>>>> linux
>>>> =====
>>>> 64-bit
>>>> ro space:   8433480 [ 37.8% of total] out of  16777216 bytes [50.3%
>>>> used] at 0x0000000800000000
>>>> rw space:  11418608 [ 51.1% of total] out of  16777216 bytes [68.1%
>>>> used] at 0x0000000801000000
>>>>
>>>> 32-bit
>>>> ro space:   6316488 [ 48.9% of total] out of  12582912 bytes [50.2%
>>>> used] at 0x80000000
>>>> rw space:   5794312 [ 44.9% of total] out of  12582912 bytes [46.0%
>>>> used] at 0x80c00000
>>>>
>>>> ========
>>>> windows
>>>> ========
>>>> 64-bit
>>>> ro space:   7888680 [ 37.7% of total] out of  16777216 bytes [47.0%
>>>> used] at 0x0000000800000000
>>>> rw space:  10704496 [ 51.1% of total] out of  16777216 bytes [63.8%
>>>> used] at 0x0000000801000000
>>>>
>>>> 32-bit
>>>> ro space:   6030640 [ 49.3% of total] out of  12582912 bytes [47.9%
>>>> used] at 0x14690000
>>>> rw space:   5440904 [ 44.5% of total] out of  12582912 bytes [43.2%
>>>> used] at 0x15290000
>>>>
>>>> ====
>>>> mac
>>>> ====
>>>> 64-bit
>>>> ro space:   6798968 [ 37.0% of total] out of  16777216 bytes [40.5%
>>>> used] at 0x0000000800000000
>>>> rw space:   9446240 [ 51.4% of total] out of  16777216 bytes [56.3%
>>>> used] at 0x0000000801000000
>>>>
>>>> ====
>>>>
>>>> So maybe we can define some enums as follows and leave the default
>>>> values in globals.hpp alone?
>>>>
>>>> min_ro_size  NOT_LP64(7*M) LP64_ONLY(9*M)
>>>> min_rw_size  NOT_LP64(6*M) LP64_ONLY(12*M)
>>>
>>> Sounds good to me.
>>>
>>> Thanks,
>>> Jiangli
>>>
>>>>
>>>> thanks,
>>>> Calvin
>>>>
>>>>>
>>>>> Thanks,
>>>>> Jiangli
>>>>>
>>>>> On 12/01/2014 12:10 PM, Calvin Cheung wrote:
>>>>>> JBS: https://bugs.openjdk.java.net/browse/JDK-8065050
>>>>>>
>>>>>> Adding more checks on the SharedMiscDataSize, ShareReadOnlySize,
>>>>>> and SharedReadWriteSize.
>>>>>>
>>>>>> For the SharedMiscDataSize, it is based on
>>>>>> MetaspaceShared::generate_vtable_methods(). Similar to what was
>>>>>> done for the SharedMiscCodeSize.
>>>>>>
>>>>>> For the ShareReadOnlySize and SharedReadWriteSize, I'm checking if
>>>>>> they are at least the default size.
>>>>>> I think it's reasonable to enforce the ro and rw sizes to be at
>>>>>> least the default size. A default dump of CDS archive requires >8M
>>>>>> of ro space and >11M of rw space.
>>>>>>
>>>>>> webrev:
>>>>>>     http://cr.openjdk.java.net/~ccheung/8065050/webrev/
>>>>>>
>>>>>> tests:
>>>>>>     ran the testcase via jtreg on linux_x64 and windows_x64
>>>>>>     JPRT
>>>>>>
>>>>>> thanks,
>>>>>> Calvin
>>>>>
>>>>
>>>
>>