RFR (M) JDK-8151178: Move the collection set out of the G1 collector policy

Mikael Gerdin mikael.gerdin at oracle.com
Mon Mar 7 09:46:49 UTC 2016

Hi all,

Here's a new version of the webrev based on feedback from Jesper and Tom.


The incremental layout is similar to version1, with the addition of 
webrev_4 which contains the review changes.

In this update I also took the liberty to change G1CollectionSet to 
become a value member in G1CollectedHeap instead of a separately C-heap 
allocated object. I see no value in it being allocated separately.


On 2016-03-04 09:35, Mikael Gerdin wrote:
> Hi all,
> As part of an attempt to make it easier for G1 to contain multiple
> collector policies I suggest that the collection set code should be
> moved out of the current G1 collector policy class into a class of its own.
> I've tried to hold back on doing further cleanups in this patch in order
> to make it easier to review the changes.
> I do have some ideas on how the collection set code could be further
> cleaned up but I'm not sure if I will have time to test them properly
> before FC.
> Webrev:
> http://cr.openjdk.java.net/~mgerdin/8151178/version1/webrev_full
> I've also split the change into three webrevs in the version1 directory:
> webrev_1 consists of moving the code and changing code accessing
> collection set related methods
> webrev_2 consists of renaming almost all methods in the new class to not
> contain redundant collection set naming
> webrev_3 restores the functionality for collector policy extensions to
> hook into collection set selection.
> Bug:
> https://bugs.openjdk.java.net/browse/JDK-8151178
> Testing: JPRT, RBT GC testing.
> Thanks6
> /Mikael

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