RFR(XXS): 8036091: compiler/membars/DekkerTest.java fails with -XX:CICompilerCount=1
albert.noll at oracle.com
Mon Mar 3 23:29:31 PST 2014
thanks for your review. I did your proposed changes.
Here is the new webrev:
On 03/03/2014 09:31 PM, Vladimir Kozlov wrote:
> You need to add -XX:-TieredCompilation to test's commands. I forgot it
> when I added the test. Removing -XX:CICompilerCount=1 is wrong because
> sequence of C2 compilations will affect the reproduction of the
> problem. CICompilerCount=1 serializes compilations and makes
> compilation sequence more deterministic. Even with -Xbatch tests which
> execute several threads the compilation is not deterministic because
> compilation requests from different java threads will be served by
> different compiler threads.
> CICompilerCount, by definition and by the code we used in Tiered, is
> total number of compilers threads, C1+C2. You can't interpret it
> differently for =1 case.
> Albert, make sure to allow CICompilerCount=1 with Tiered compilation
> when only C1 is used (TieredStopAtLevel < 4).
> On 3/3/14 4:49 AM, Aleksey Shipilev wrote:
>> Thanks Albert!
>> P.S. Serves me right for not paying attention to the original issue
>> thinking it only covers the negative values.
>> On 03/03/2014 04:47 PM, Albert wrote:
>>> Hi Aleksey,
>>> Vladimir K. reviewed JDK-8034775, let's see what he thinks. If we
>>> to go for the clean
>>> solution, I could make it work.
>>> On 03/03/2014 01:42 PM, Aleksey Shipilev wrote:
>>>> On 03/03/2014 04:25 PM, Albert wrote:
>>>>> For me the only clean solution that *enforces* and *retains* the
>>>>> meaning of the flag is to enable a compiler thread to grab tasks from
>>>>> both queues (or have a shared queue). Maybe someone can tell why it
>>>>> is implemented as it is?
>>>> I agree, this seems to be only good solution for
>>>> not-that-familiar-with-HS-tiered-arch guy like me.
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