Request for review: 7117052 instanceKlass::_init_state can be u1 type

[David Holmes]

On 7/12/2011 5:23 AM, Jiangli Zhou wrote:
> Hi David and Tom,
>
> I ran nsk/sajdi/ tests for the class state changes. Comparing to a
> baseline, there is no new failure in those tests.
>
> The changes do not seem to have noticeable performance impact. Specjvm98
> shows only noise variation (-0.06 ~ 0.39).

Something more classloading intensive might be a better choice - specjbb 
perhaps? I'm not sure which benchmarks exercise which facilities the most.

Thanks,
David
-----

> ==============================================================================
>
> logs.baseline:
> Benchmark Samples Mean Stdev Geomean Weight
> specjvm98 3 264.56 4.50
> ==============================================================================
>
> logs.1:
> Benchmark Samples Mean Stdev %Diff P Significant
> specjvm98 3 264.41 11.12 -0.06 0.984 *
> ==============================================================================
>
>
>
> ==============================================================================
>
> logs.baseline:
> Benchmark Samples Mean Stdev Geomean Weight
> specjvm98 3 264.56 4.50
> ==============================================================================
>
> logs.1.2:
> Benchmark Samples Mean Stdev %Diff P Significant
> specjvm98 3 265.61 4.92 0.39 0.800 *
> ==============================================================================
>
>
>
> Thanks,
> Jiangli
>
>
> On 12/06/2011 10:10 AM, Tom Rodriguez wrote:
>> You can run them using ute,
>> /net/sqenfs-1.us.oracle.com/export1/tools/gtee/bin/ute. Use -jdk to
>> specify the test JDK, -vmopts to pass any options and -test select a
>> suite. nsk/sajdi/ and tmtools/ are the main ones that exercise the SA.
>> nsk/sajdi has quite a few known failures so it can be tricky to
>> evaluate the results.
>>
>> tom
>>
>> On Dec 5, 2011, at 5:21 PM, Jiangli Zhou wrote:
>>
>>> Hi David,
>>>
>>> Thanks for the review and suggestions. Could you please let me know
>>> where I can find SA tests and instructions for running those tests?
>>>
>>> I'm double check the performance impact.
>>>
>>>
>>> Thanks,
>>> Jiangli
>>>
>>> On 12/04/2011 06:17 PM, David Holmes wrote:
>>>> On 3/12/2011 4:55 AM, Jiangli Zhou wrote:
>>>>> Hi David,
>>>>>
>>>>> Thanks for catching that. I changed the debug version of
>>>>> set_init_state(). The updated webrev is
>>>>> http://cr.openjdk.java.net/~jiangli/7117052/webrev.01/.
>>>> Thanks - that update looks fine.
>>>>
>>>> Have you run SA tests to confirm no impact on SA code?
>>>>
>>>> Have you run any performance tests?
>>>>
>>>> David
>>>> -----
>>>>
>>>>> Thanks,
>>>>>
>>>>> Jiangli
>>>>>
>>>>> On 12/01/2011 05:18 PM, David Holmes wrote:
>>>>>> As already mentioned in internal email, there seem to be changes
>>>>>> missing for debug builds. In instanceKlass set_init_state has two
>>>>>> implementations - one for product and one for debug. The debug
>>>>>> version
>>>>>> has not been modified to accommodate the change in type.
>>>>>>
>>>>>> David
>>>>>>
>>>>>> On 2/12/2011 4:51 AM, Jiangli Zhou wrote:
>>>>>>> The instanceKlass::_init_state is defined as
>>>>>>> instanceKlass::ClassState
>>>>>>> type, which is an enum. Currently there are 7 class states
>>>>>>> defined. The
>>>>>>> instanceKlass::_init_state can be changed to u1 type, which could
>>>>>>> hold
>>>>>>> up 256 states. There are unused bytes after
>>>>>>> instanceKlass::_idnum_allocated_count field. Changing _init_state
>>>>>>> to u1
>>>>>>> and move it to after the _idnum_allocate_count field would save
>>>>>>> 4-byte
>>>>>>> for each loaded class.
>>>>>>>
>>>>>>> http://cr.openjdk.java.net/~jiangli/7117052/webrev.00/
>>>>>>>
>>>>>>> Thanks,
>>>>>>>
>>>>>>> Jiangli
>>>>>>>
>