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

Jamsheed C m jamsheed.c.m at oracle.com
Mon Jan 16 15:41:58 UTC 2017 

Hi Vladimir,

as per internal discussion, made following changes

1) The default VM ergonomics on Windows/x86 (32-bit) are changed to 
client like(client compiler, SerialGC, Xshare:auto). No new flag 
provided to switch to server mode.

2) -XX:+|-TieredCompilation switch to server mode.

revised webrev:

hotspot part: http://cr.openjdk.java.net/~jcm/8166002/webrev.06/

root hs part: http://cr.openjdk.java.net/~jcm/8166002/webrev.06.hs/

CCC request will be withdrawn.

Best Regards,

Jamsheed

On 1/10/2017 10:02 AM, Jamsheed C m wrote:
> Hi Vladimir,
>
> On 1/10/2017 12:57 AM, Vladimir Kozlov wrote:
>> Hi, Jamsheed
>>
>> Why you set flags related to segmented codecache? 
>> NonProfiledCodeHeapSize, ProfiledCodeHeapSize, NonNMethodCodeHeapSize
> i made setting more equivalent to c1_globals_XX.hpp non tiered settings.
>>
>> SegmentedCodeCache should be off in Client mode. SegmentedCodeCache 
>> setting is done in set_tiered_flags() which is called after you 
>> changed ReservedCodeCacheSize in set_client_compilation_mode() and 
>> will not be set to true.
> Yeah.
>>
>> Unfortunately we can do nothing for CodeCacheSegmentSize which is 128 
>> bytes in tiered VM since it is constant in product VM.
> Ok.
>>
>> I also forgot to tell that you should use FLAG_SET_ERGO() macro for 
>> flags settings in set_client_compilation_mode().
> Ok.
> Best Regards,
> Jamsheed
>>
>> Thanks,
>> Vladimir
>>
>> On 1/3/17 9:56 AM, Vladimir Kozlov wrote:
>>> Good.
>>>
>>> Thanks,
>>> Vladimir
>>>
>>> On 1/3/17 8:17 AM, Jamsheed C m wrote:
>>>> Hi Vladimir,
>>>>
>>>> On 1/3/2017 11:15 AM, Vladimir Kozlov wrote:
>>>>> Hi Jamsheed
>>>>>
>>>>> Why you moved set_client_compilation_mode() to c1_globals and new
>>>>> class? Why not to keep it in compilerDefinitions?
>>>>>
>>>> Done.
>>>>> selected_with_other_flags setting and code in
>>>>> compilation_mode_selected() have the same checks - factor them into
>>>>> one function.
>>>> Done.
>>>>>
>>>>> I would suggest to keep comment in compilationPolicy.cpp.
>>>> Done.
>>>> revised webrev: http://cr.openjdk.java.net/~jcm/8166002/webrev.05/
>>>>
>>>> Best Regards,
>>>> Jamsheed
>>>>>
>>>>> I reviewed CCC request.
>>>>>
>>>>> Thanks,
>>>>> Vladimir
>>>>>
>>>>> On 1/2/17 8:25 PM, Jamsheed C m wrote:
>>>>>> Hi Vladimir, Igor,
>>>>>>
>>>>>> i changed implementation a little bit(i.e now more close to -client
>>>>>> behavior). Tests are modified to support this mode.
>>>>>>
>>>>>> http://cr.openjdk.java.net/~jcm/8166002/webrev.04/
>>>>>>
>>>>>>
>>>>>> A new command-line option -XX:CompilationMode=<server/client> will
>>>>>> be provided in JDK 9 to emulate a client build on
>>>>>> 32-bit Windows platforms using a standard tiered build.
>>>>>>
>>>>>> -XX:CompilationMode=server--selects to build time compilation mode
>>>>>> of server VM.
>>>>>> -XX:CompilationMode=client--selects non-tiered c1 compiler. (Serial
>>>>>> Garbage Collection in ON and Xshare is set to auto
>>>>>> in this mode).
>>>>>>
>>>>>> This option is available only on Tiered build (i.e. Server VM).
>>>>>> Client VM ignores this flag and continues with build time
>>>>>> compilation mode.
>>>>>>
>>>>>> This option will have no effect if any of TieredCompilation,
>>>>>> TieredStopAtLevel, UseAOT, EnableJVMCI, UseJVMCICompiler is
>>>>>> specified at the command-line.
>>>>>>
>>>>>> Platforms except 32-bit Windows runs in server compilation mode by
>>>>>> default. 32-bit Windows runs in client compilation
>>>>>> mode by default. The user should specify
>>>>>> -XX:CompilationMode=<server/client> to switch.
>>>>>>
>>>>>> -XX:+/-TieredCompilation or -XX:TieredStopAtLevel=<0-4> or
>>>>>> -XX:+/-UseAOT or -XX:+/-EnableJVMCI or
>>>>>> -XX:+/-UseJVMCICompiler always switch to build time compilation mode
>>>>>> plus corresponding option behavior irrespective of
>>>>>> CompilationMode option.
>>>>>>
>>>>>> I have updated the CCC request link in bug report, Please review.
>>>>>>
>>>>>> Best Regards,
>>>>>> Jamsheed
>>>>>>
>>>>>> On 12/6/2016 12:22 AM, Vladimir Kozlov wrote:
>>>>>>> On 12/5/16 6:21 AM, Jamsheed C m wrote:
>>>>>>>> Hi Vladimir,
>>>>>>>>
>>>>>>>> On 12/3/2016 8:02 AM, Vladimir Kozlov wrote:
>>>>>>>>> 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?
>>>>>>>> This one.
>>>>>>>
>>>>>>> I see.
>>>>>>>
>>>>>>> Thanks,
>>>>>>> Vladimir
>>>>>>>
>>>>>>>> src/share/vm/c1/c1_Compilation.hpp
>>>>>>>>
>>>>>>>>   // will compilation make optimistic assumptions that might 
>>>>>>>> lead to
>>>>>>>>     // deoptimization and that the runtime will account for?
>>>>>>>>     bool is_optimistic() const                             {
>>>>>>>> - return !TieredCompilation &&
>>>>>>>> + return is_client_compilation_mode_vm() &&
>>>>>>>>         (RangeCheckElimination || UseLoopInvariantCodeMotion) &&
>>>>>>>> method()->method_data()->trap_count(Deoptimization::Reason_none)
>>>>>>>> == 0;
>>>>>>>>     }
>>>>>>>>
>>>>>>>> src/share/vm/c1/c1_Runtime1.cpp
>>>>>>>> - assert(!TieredCompilation, "incompatible with tiered 
>>>>>>>> compilation");
>>>>>>>> + assert(is_client_compilation_mode_vm(), "incompatible in non
>>>>>>>> client modes");
>>>>>>>>
>>>>>>>> mpegaudio was about 6% low without this.
>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> 2) Made SerialGC as default GC.
>>>>>>>>>
>>>>>>>>> Should be only for client_compilation_mode
>>>>>>>> Ok.
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> 3) Set CICompileCount=1 for client compilation mode.
>>>>>>>>>
>>>>>>>>> I think check should be is_client_compilation_mode_vm()
>>>>>>>> Ok.
>>>>>>>> Best Regards,
>>>>>>>> Jamsheed
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> 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
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>
>>>>>>
>>>>
>

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