JEP 147: Reduce Class Metadata Footprint
fweimer at bfk.de
Thu Mar 1 01:33:16 PST 2012
* David Holmes:
> On 1/03/2012 5:49 PM, Florian Weimer wrote:
>>> Posted: http://openjdk.java.net/jeps/147
>> This part:
>> | - Limit the number of mallocs, and the resultant per-malloc block
>> | overhead, when allocating memory for a loaded class. Most of the
>> | class is laid out in one large malloc allocation.
>> seems to overlap with JEP 122, which adds classloader-specific memory
>> allocation pools.
> JEP 122 covers where the memory will be allocated. JEP 147 tackles how
> much memory needs to be allocated.
The per-object allocation overhead depends on where it is allocated.
Depending on how the pool allocator works, reducing the number of
allocations might no longer be necessary or even counterproductive (due
to increased fragmentation).
Florian Weimer <fweimer at bfk.de>
BFK edv-consulting GmbH http://www.bfk.de/
Kriegsstraße 100 tel: +49-721-96201-1
D-76133 Karlsruhe fax: +49-721-96201-99
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