RFR: JDK-8166648,,jib make run-test for langtools results in intermittent failures on windows-x86

[Jonathan Gibbons]

Looks good to me.

FWIW, I recommend developers using -Xmx512 for these tests, but I think 
it is a good idea to be somewhat more lax/generous on automated build 
platforms, to avoid spurious failures.

-- Jon

On 10/07/2016 06:34 PM, Tim Bell wrote:
> Hi Jon
>
> On 10/07/16 15:48, Jonathan Gibbons wrote:
>> Tim,
>>
>> The problem only appears on 32-bit Windows, but the fix appears to be
>> across the board.
>> Does this penalize or otherwise adversely affect test runs on other
>> platforms?
>
> Good point.  Here is an updated webrev where serialGC is requested 
> only on 32 bit platforms:
>
>    http://cr.openjdk.java.net/~tbell/8166648/webrev.01/
>
> This change tested OK in JPRT on the following platforms:
>   solaris_sparcv9_5.11-product-c2-langtools_jtreg
>   solaris_x64_5.11-product-c2-langtools_jtreg
>   linux_i586_3.8-product-c2-langtools_jtreg
>   linux_x64_3.8-product-c2-langtools_jtreg
>   macosx_x64_10.9-product-c2-langtools_jtreg
>   windows_i586_6.3-product-c2-langtools_jtreg
>   windows_x64_6.3-product-c2-langtools_jtreg
>
> I inspected the test logs to verify -XX:+UseSerialGC is passed only 
> during 32-bit testing.
>
> Tim
>
>>
>> -- Jon
>>
>> On 10/07/2016 07:15 AM, Tim Bell wrote:
>>> Again with the review link .. see below:
>>>
>>> On 10/07/16 06:40, Tim Bell wrote:
>>>> Hello
>>>>
>>>> The change of HotSpot runtimes on 32-bit Windows [1] has been a source
>>>> of langtools test failures due to memory space exhaustion.
>>>>
>>>> On our Windows build/test clients, the combination of the C2 
>>>> runtime and
>>>> parallel GC causes about 20 extra threads to be started in each VM.
>>>> These added thread stacks, plus heap management in C2, result in too
>>>> much memory pressure to fit the workload into 32-bit VMs.
>>>>
>>>> This fix will run langtools jtreg tests using the serial garbage
>>>> collector instead of using the default collector (parallel GC).
>>>
>>> http://cr.openjdk.java.net/~tbell/8166648/
>>>
>>>>
>>>> Testing:
>>>>    -5 out of 5 jobs (with the fix) passed langtools testing
>>>>    -4 out of 5 control jobs (without the fix) failed testing in
>>>> windows_i586_6.3-product-c2-langtools_jtreg
>>>>
>>>>
>>>> Thanks in advance-
>>>>
>>>> Tim
>>>>
>>>> [1] JDK-8154209 "Remove client VM from default JIB profile on
>>>> windows-x86 and linux-x86"
>>>> https://bugs.openjdk.java.net/browse/JDK-8154209
>>>
>>
>