RFR: Cease JDK 10 support for Shenandoah

[Roman Kennke]

It's ok by me.

Roman


> Seems only a few people need it. I would like to go forward with ceasing support.
> 
> This is the last call for comments about the need to keep Shenandoah JDK 10 backport supported.
> 
> -Aleksey
> 
> On 09/19/2018 10:35 AM, Aleksey Shipilev wrote:
>> Gauging public interest here as well:
>>   https://twitter.com/shipilev/status/1042330798798585856
>>
>> -Aleksey
>>
>> On 09/19/2018 10:27 AM, Aleksey Shipilev wrote:
>>> Upstream had ceased to publish any fixes to 10u, and 11 is going to be released next week. sh/jdk11
>>> is stable enough for adopters to use. In fact, many adopters who prefer the up-to-date JDKs already
>>> do use sh/jdk11. We also have quite substantial cleanup/backports coming, especially in compiler
>>> area. All of the above makes sh/jdk10 support dubious, and I propose we cease it.
>>>
>>> Like with sh/jdk9 before, let us print the warning message on startup:
>>>
>>> diff -r 82f1eec5affa src/hotspot/share/gc/shenandoah/shenandoahArguments.cpp
>>> --- a/src/hotspot/share/gc/shenandoah/shenandoahArguments.cpp   Mon Sep 10 17:56:38 2018 +0200
>>> +++ b/src/hotspot/share/gc/shenandoah/shenandoahArguments.cpp   Wed Sep 19 10:22:47 2018 +0200
>>> @@ -29,10 +29,16 @@
>>>  #include "gc/shenandoah/shenandoahCollectorPolicy.hpp"
>>>  #include "gc/shenandoah/shenandoahHeap.hpp"
>>>  #include "utilities/defaultStream.hpp"
>>>
>>>  void ShenandoahArguments::initialize_flags() {
>>> +  log_warning(gc)("**************************************************************************");
>>> +  log_warning(gc)("*  Shenandoah GC support for this JDK release had ceased.                *");
>>> +  log_warning(gc)("*  JDK 10 is a short-term release, and it had reached end of life.       *");
>>> +  log_warning(gc)("*  This JDK would not get security, functionality or performance fixes.  *");
>>> +  log_warning(gc)("*  Use this build at your own risk, and consider migrating to next JDK.  *");
>>> +  log_warning(gc)("**************************************************************************");
>>>
>>>  #if !(defined AARCH64 || defined AMD64 || defined IA32)
>>>    vm_exit_during_initialization("Shenandoah GC is not supported on this platform.");
>>>  #endif
>>>
>>> Testing: tier1_gc_shenandoah
>>>
>>> Thanks,
>>> -Aleksey
>>>
>>
>>
> 
>