RFR (XS): 8005108: NPG: Add specialized Metachunk sizes for reflection and anonymous classloaders
jon.masamitsu at oracle.com
Tue Dec 18 08:30:53 PST 2012
On 12/18/12 04:16, Stefan Karlsson wrote:
> On 12/18/2012 11:47 AM, Bengt Rutisson wrote:
>> Hi Stefan,
>> Looks good to me.
>> I think this comment in metaspace.cpp can also be removed:
>> 2220 // The total words available for metadata allocation. This
>> 2221 // uses Metaspace capacity_words() which is the total words
>> 2222 // in chunks allocated for a Metaspace.
> My change just reverses some of the changes in 3854. This comment was
> already wrong before that change.
> Jon, do you think I should remove or reword the comment.
Please remove the comment. The name of the method is
Also, change looks good.
>> On 12/18/12 11:02 AM, Stefan Karlsson wrote:
>>> Description from the bug:
>>> The implementation of MetaspaceAux::used_in_bytes(),
>>> capacity_in_bytes() and reserved_in_bytes() changed as part of this
>>> changeset: 3854:90273fc0a981
>>> user: coleenp
>>> date: Thu Nov 29 16:50:29 2012 -0500
>>> summary: 8000662: NPG: nashorn ant clean test262 out-of-memory with
>>> Java heap
>>> Before this change it seems like data + classes = total. After this
>>> does not seem to hold.
>>> This can be verified by running a simple test that does System.gc()
>>> with -XX:+PrintHeapAtGC:
>>> Change 3853:
>>> Metaspace total 3400K, used 2760K, reserved 108544K
>>> data space 3076K, used 2477K, reserved 6144K
>>> class space 324K, used 283K, reserved 102400
>>> Change 3854:
>>> Metaspace total 3400K, used 3400K, reserved 108544K
>>> data space 3076K, used 2476K, reserved 6144K
>>> class space 324K, used 283K, reserved 102400K
>>> In this example capacity and reserved add up, but used does not. I
>>> have seen cases where at least capacity also did not add up.
>>> This patch reverts back to the old implementation. We probably want
>>> a better way to count these values, but right now we need consistent
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