8169001: Remove launcher's built-in ergonomics

[David Holmes]

Looks good!

Thanks,
David

On 11/11/2016 7:10 AM, Kumar Srinivasan wrote:
> Hi David,
>
> Here is the updated revision
> * added back in FreeUnknowVMS
> * add -client KNOWN as you suggested
>
> delta webrev
> http://cr.openjdk.java.net/~ksrini/8169001/webrev.01/webrev.delta/
>
> full webrev (for reference):
> http://cr.openjdk.java.net/~ksrini/8169001/webrev.01/
>
> Thanks
> Kumar
>
>
>
>
> On 11/7/2016 3:24 PM, David Holmes wrote:
>> Hi Kumar,
>>
>> On 8/11/2016 4:47 AM, Kumar Srinivasan wrote:
>>>
>>> Hello,
>>>
>>> Please review the fix for:
>>> https://bugs.openjdk.java.net/browse/JDK-8169001
>>>
>>> Webrev at:
>>> http://cr.openjdk.java.net/~ksrini/8169001/webrev.00/
>>
>> Overall this looks like a complete eradication of the launcher
>> ergonomics. A few specific comments:
>>
>> src/java.base/share/native/launcher/main.c
>>
>> !                    const_cpwildcard, const_javaw, 0);
>>
>> Can you clarify this change with
>>
>> !                    const_cpwildcard, const_javaw, 0 /* unused */);
>>
>> Thanks.
>>
>> ---
>>
>> src/java.base/share/native/libjli/java.c
>>
>>  220         jint ergo                               /* unused */
>>
>> I assume JLI_Launch is an exported API otherwise I'd expect this to be
>> deleted. The fact it is unused should also be documented in
>> src/java.base/share/native/libjli/java.h. But I'm also wondering where
>> this API change is being documented for external users?
>>
>> -     FreeKnownVMs();  /* after last possible PrintUsage() */
>>
>> Not clear why you no longer need to free here. But if you don't then
>> FreeKnownVMs() seems to be dead code now.
>>
>> ---
>>
>> src/java.base/unix/conf/i586/jvm.cfg
>>
>> I think you still need an entry for "-client KNOWN" as anyone can
>> build the client VM if they choose. Ditto for
>> src/java.base/unix/conf/sparc/jvm.cfg (though 32-bit Solaris builds
>> are obsolete now).
>>
>> ---
>>
>> You have updated a number of copyright notices but not all of them.
>>
>> ---
>>
>> I see no changes to tests, but I'm pretty sure we have a test for
>> server-class-machine somewhere (or we did - I recall it breaking at
>> some point).
>>
>> Thanks,
>> David
>>
>>> Background:
>>>> Launcher ergonomics was introduced last decade to help determine
>>>> if the execution system is "Server Class", this was necessary to
>>>> choose server VM on platforms that supported both client and server
>>>> VMs (primarily for Solaris and Linux 32-bit).
>>>>
>>>> The algorithm involves computing and detecting the number of CPUs
>>>> and the amount of memory on the target system. All modern computers
>>>> systems with hyper-threading cause the ergonomics to choose server.
>>>>
>>>> JDK9 Platforms that have only server vm.
>>>>
>>>> ./linux-x64/lib/amd64/server/libjvm.so
>>>> ./linux-arm64-vfp-hflt/lib/aarch64/server/libjvm.so
>>>> ./solaris-sparcv9/lib/sparcv9/server/libjvm.so
>>>> ./solaris-x64/lib/amd64/server/libjvm.so
>>>> ./windows-x86/bin/server/jvm.dll
>>>> ./windows-x64/bin/server/jvm.dll
>>>>
>>>> JDK9 Platforms that have more than one vm variant:
>>>> ./linux-arm32-vfp-hflt/lib/arm/client/libjvm.so (default)
>>>> ./linux-arm32-vfp-hflt/lib/arm/minimal/libjvm.so
>>>>
>>>> ./linux-x86/lib/i386/server/libjvm.so (default)
>>>> ./linux-x86/lib/i386/minimal/libjvm.so
>>>>
>>>>
>>>> In the cases where multiple VMs are supported the ergnomics
>>>> has no effect, and the default platforms are chosen by the
>>>> jvm.cfg. Thus the launcher ergonomics is obsolete and redundant.
>>>
>>> Thanks
>>> Kumar
>>>
>