Preventing Class Definitions from Compacting At GC Cycle

[姜善林]

Hi all,

I'm sorry if this email bothers you. Just one question, is there any way to
determine precisely the regression test scope for java development and
testing?

Many thanks!


2013/11/4 David Holmes <david.holmes at oracle.com>

> Adding hotspot-gc and (hopefully) bcc'ing the discuss list.
>
> David
>
> On 3/11/2013 5:18 AM, serkan özal wrote:
>
>> Hi all,
>> I am not sure that target of mail is this group or not but I don't know
>> better one for asking :)
>> I am currently working on an OffHeap solution and I have a problem with
>> "Compact" phase of GC.As I see at "Compact" phase, location of classes
>> these not loaded by bootloader may be changed. However, location of classes
>> these loaded by bootloader (classloaders are null) are not changed.Changing
>> memory location of class definition fails my OffHeap solution.
>> Compacting can be disabled by VM arguments but I don't want to use these
>> arguments. Because disabling compaction for all objects causes increasing
>> of fragmentation. In addition, I tried class pinning with JNI by
>> "NewGlobalRef" method but it doesn't prevent compacting. As I understood,
>> it only hides object from garbage collected.
>> In brief, is there any way to prevent compacting of any specific class
>> defition (or object) at GC cycle?Is there any bit, offset or field (such as
>> mark_oop) in object header to prevent compacting of fully from GC for any
>> specific object or class?
>> Thanks in advance.
>> --
>> Serkan ÖZAL
>>
>>
>>


-- 
姜善林
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