RFR(L): 8075506: aix: improve handling of native memory

[Thomas Stüfe]

Hi Valdimir, Goetz,

sorry, the comment is misleading. What was meant was that no explicit
commit is needed, on AIX we have automatic commit on touch. Which is
actually true for all memory, not just C heap. So though it is true that
pthread stacks live in C heap, it does not matter here and the comment
should be changed to "On AIX we need no explicit commit".

@Goetz:

Changes look ok, build ok and 64k pages are allocated now (tested with
-XX:+Verbose). Thank you for porting this to the OpenJDK!

There are some changes in there which have nothing to do with 64K page
support:
- anything in create_stack_guard_pages() and allocate_stack_guard_pages()
- attachListener.cpp, interfaceSupport.hpp and perfMemory_aix.cpp
this all could go to a separate patch. Or, we just label the patch as
generic patch collection.

Regards, Thomas







On Wed, Mar 25, 2015 at 6:53 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com
> wrote:

> Looks good. I only glanced through os_aix.cpp changes - they look fine
> from 'glance'.
>
> Could you explain a little about allocate_stack_guard_pages() returning
> false? The comment say that you are not using normal C stack. Is it true?
>
> Thanks,
> Vladimir
>
>
> On 3/25/15 1:22 AM, Lindenmaier, Goetz wrote:
>
>> Hi,
>>
>> this change improves handling of native memory on aix.  It adds support
>> for
>> 64K pages and allocation at requested addresses.  This improves
>> performance
>> by a few percent.
>>
>> Please review this change.  It is aix-only.
>> http://cr.openjdk.java.net/~goetz/webrevs/8075506-aixMem/webrev.00/
>>
>> Best regards,
>>    Goetz.
>>
>>