RFR: 8166002: Emulate client build on platforms with reduced virtual address space

[Vladimir Kozlov]

On 12/2/16 7:38 AM, Jamsheed C m wrote:
> Hi Vladimir, Igor,
>
> I made a few more changes to include the optimization that was available only on client.
>
> 1) a few c1 changes (JDK-7153771..)

Which one?

>
> 2) Made SerialGC as default GC.

Should be only for client_compilation_mode

>
> 3) Set CICompileCount=1 for client compilation mode.

I think check should be is_client_compilation_mode_vm()

>
> 4) Tuned thresholds to get better performance.

ok

>
> 5) Added relevant flags in few tests, modified TestSelectDefaultGC.java.

ok

Thanks,
Vladimir

>
> revised webrev: http://cr.openjdk.java.net/~jcm/8166002/webrev.03/
>
> performance report is added in bug report.
>
> Best Regards,
>
> Jamsheed
>
>
>
> On 11/1/2016 1:14 AM, Vladimir Kozlov wrote:
>> webrev.02 looks good to me too.
>>
>> Thanks,
>> Vladimri
>>
>> On 10/31/16 10:39 AM, Igor Veresov wrote:
>>> Jamsheed explained to me that ReservedCodeCacheSize is now set in the else clause (udiffs are not showing the proper alignment and I missed it). The change looks good to me.
>>>
>>> igor
>>>
>>>> On Oct 31, 2016, at 9:42 AM, Igor Veresov <igor.veresov at oracle.com> wrote:
>>>>
>>>> Assuming it gets the performance/startup numbers close to the client VM it looks fine.
>>>> But what about adjusting the code cache sizes? With tiered we get 240M ReservedCodeCacheSize, which also turns on SegmentedCodeCache. It seems like we won’t need the “profiled” segment of the code
>>>> cache at all. It is also likely that we’d do fine with a smaller overall code cache.
>>>>
>>>> igor
>>>>
>>>>> On Oct 31, 2016, at 9:14 AM, Jamsheed C m <jamsheed.c.m at oracle.com> wrote:
>>>>>
>>>>> Hi Vladimir, Igor,
>>>>>
>>>>> revised webrev: http://cr.openjdk.java.net/~jcm/8166002/webrev.02/
>>>>>
>>>>> i took flags from bug comment.
>>>>>
>>>>> Igor V. suggested next flags setting to emulate Client VM compile threshold with TieredStopAtLevel=1:
>>>>>
>>>>> Tier3BackEdgeThreshold=14000
>>>>> Tier3CompileThreshold=1500
>>>>> Tier3InvocationThreshold=1500
>>>>> Tier3MinInvocationThreshold =1500
>>>>>
>>>>> Best Regards,
>>>>>
>>>>> Jamsheed
>>>>>
>>>>> On 10/28/2016 11:48 PM, Vladimir Kozlov wrote:
>>>>>> Add comment what the code does and why. Move the code into separate function reaturning bool. And condition CodeCache setting based on result. It will reduce #ifdef mess.
>>>>>>
>>>>>> Can you put && to the end of previous line? To get good alignment.
>>>>>> Should we also change CompilationPolicyChoice?
>>>>>>
>>>>>> Ask Igor Veresov to verify settings.
>>>>>>
>>>>>> Thanks,
>>>>>> Vladimir
>>>>>>
>>>>>> On 10/28/16 10:59 AM, Jamsheed C m wrote:
>>>>>>> Hi Vladimir,
>>>>>>>
>>>>>>> revised webrev with just ergo settings for win32.
>>>>>>>
>>>>>>> http://cr.openjdk.java.net/~jcm/8166002/webrev.01/
>>>>>>>
>>>>>>> Best Regards
>>>>>>>
>>>>>>> Jamsheed
>>>>>>>
>>>>>>>
>>>>>>> On 10/28/2016 12:25 PM, Vladimir Kozlov wrote:
>>>>>>>> Hi Jamsheed,
>>>>>>>>
>>>>>>>> Why you need changes in tests?
>>>>>>>>
>>>>>>>> Why you can't use set_client_compilation_mode() in both places?
>>>>>>>>
>>>>>>>> Looks fine otherwise.
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Vladimir
>>>>>>>>
>>>>>>>> On 10/20/16 8:45 AM, Jamsheed C m wrote:
>>>>>>>>> Hi All,
>>>>>>>>>
>>>>>>>>> bug id:https://bugs.openjdk.java.net/browse/JDK-8166002
>>>>>>>>>
>>>>>>>>> http://cr.openjdk.java.net/~jcm/8166002/webrev.00/
>>>>>>>>>
>>>>>>>>> Fix: set NeverActAsServerClassMachine=true, Limit TieredCompilation to C1 by default, for win32 platform.
>>>>>>>>>
>>>>>>>>> A new flag CompilationMode=<client/server> is introduced to select server/ client mode compilation. This option is supported only in TIERED builds.
>>>>>>>>>
>>>>>>>>> -XX:CompilationMode=server supports both -XX:+/-TieredCompilation.
>>>>>>>>>
>>>>>>>>> -XX:CompilationMode:client ignores TieredCompilation flag.
>>>>>>>>>
>>>>>>>>> Please review,
>>>>>>>>>
>>>>>>>>> Best Regards,
>>>>>>>>>
>>>>>>>>> Jamsheed
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>
>>>>>
>>>>
>>>
>