Binary Tree listing question

Y.S.Ramakrishna at Sun.COM Y.S.Ramakrishna at Sun.COM
Wed Aug 5 14:03:38 PDT 2009


The first is for the CMS Old Gen and the second for the
CMS Perm Gen space, where all of the space is allocated
linearly out of a single contiguous block, leaving nothing in the
tree (effectively, the perm gen allocator uses a linear allocator
with nothing in the size-keyed binary tree initially, although
i think that eventually you will end up populating this tree
when you collect the perm gen; compaction will revert it back
to a linear allocator. This choice of allocator is buried in
history.)

-- ramki

On 08/05/09 12:53, Maslowski, Chuck wrote:
> Using JDK 1.6.0_14 (perf 1 rel)
> 
> Can you please explain why we get 2 of these listings every time and the 
> 2^nd one always has only zeroes ?
> 
> Thanks
> 
> Chuck Maslowski / CBOE
> 
>  
> 
>  
> 
> Statistics for BinaryTreeDictionary:
> 
> ------------------------------------
> 
> Total Free Space: 638634712
> 
> Max   Chunk Size: 638634712
> 
> Number of Blocks: 1
> 
> Av.  Block  Size: 638634712
> 
> Tree      Height: 1
> 
> Before GC:
> 
> Statistics for BinaryTreeDictionary:
> 
> ------------------------------------
> 
> Total Free Space: 0
> 
> Max   Chunk Size: 0
> 
> Number of Blocks: 0
> 
> Tree      Height: 0
> 
>  
> 




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