RFR: 8328101: Parallel: Obsolete ParallelOldDeadWoodLimiterMean and ParallelOldDeadWoodLimiterStdDev [v2]

[Thomas Schatzl]

On Tue, 19 Mar 2024 12:11:40 GMT, Albert Mingkun Yang <ayang at openjdk.org> wrote:

>> Simple refactoring Parallel full-gc dead word calculation and removing two jvm flags.
>> 
>> Test: tier1-3
>
> Albert Mingkun Yang has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains one commit:
> 
>   pgc-dead-ratio

Changes requested by tschatzl (Reviewer).

src/hotspot/share/gc/shared/gc_globals.hpp line 623:

> 621:           "value. "                                                         \
> 622:           "Parallel full gc treats this as maximum value, i.e. a non-fully" \
> 623:           "compact full gc cycle wastes at most this value of space. "      \

Suggestion:

          "Parallel full gc treats this as maximum value, i.e. when "       \
          "allowing dead wood, Parallel full gc wastes at most this amount "\
          "of space."                                                       \

I admit I did not fully understand the original description, so this is my best guess what had been meant. First, "non-fully compact full gc cycle" sounds very awkward as "non-fully" isn't defined anywhere, and what is a full gc "cycle" wrt Parallel GC?  Also s/value/amount.

Maybe also change the term "mark sweep" for Serial to "full gc" above as well because it seems to be unnecessary to refer to the algorithm here.

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PR Review: https://git.openjdk.org/jdk/pull/18278#pullrequestreview-1948378420
PR Review Comment: https://git.openjdk.org/jdk/pull/18278#discussion_r1531769243