NewSize and SurvivorRatio needed with UseAdaptiveSizePolicy ?

[Sharma, Vipin K]

On 4/23/14 11:17 PM, Sharma, Vipin K wrote:
Hi All
 
I am working on an old java application and few days back we observed application crashed due to memory issue.
 
Below are the parameters we are using
-Xms32m -Xmx2048m -Xss1m -XX:+UseParallelGC -XX:NewRatio=2 -XX:NewSize=8m -XX:MaxNewSize=64m -XX:SurvivorRatio=25 -XX:+UseAdaptiveSizePolicy
 
Looking at these parameters few questions comes in mind and Looking for expert advice
1. When we are using UseAdaptiveSizePolicy option , what is use of NewSize , MaxNewSize , NewRatio , SurvivorRatio. Shall I remove these ? 
2. Using above options are we overriding values set by UseAdaptiveSizePolicy ?


Thanks,
Vipin Sharma

On 4/25/2014 3:01 AM, Jon Wrote:
UseAdaptiveSizePolicy affects how the heap grows and shrinks.  
UseAdaptiveSizePolicy grows and shrinks the heap within whatever
size it is given for the heap.  There are default sizes but if you
have preferred sizes, continue to use them.

Jon



Hi Jon,

My understanding from your answer is: These options will override values used by UseAdaptiveSizePolicy.

Also my Xmx is 2048m , MaxNewSize=64m  and  NewRatio=2  , it means below will be Heap structure when all parts of heap are allocated maximum memory
Young(64 M ) + Old ( 128 M) + Rest Memory only for Permanent Generation Area

I feel we are not using heap memory efficiently more than 1.8 GB is allocated for Permanent Generation only.
Is it correct understanding ?

Thanks
Vipin Sharma