RFR: 8294850: Make rs length/pending card predictors dependent on gc phase [v2]

[Thomas Schatzl]

> Hi all,
> 
>   can I have reviews for this change that separates `rs_length` and `pending_cards` predictors by young phase?
> 
> Some notes:
> * this does not intend to improve the predictors themselves - i.e. the use of `xxx_diff` and `xxx` predictors and adding them together is kind of weird, imho trying to add a kind of prediction compensation/improvement to act on differences like a (PID-)controller. I also strongly suspect that the `xxx_diff` predictors ought to be allowed to report negative values. This is no attempt to fix this
> * the parameter `for_young_gc` in the analytics API is misnamed. It's not about young gcs, but young_only_phase - I will fix this in a follow-up
> 
> Depends on PR#10649, please review that one first.
> 
> Thanks, 
>   Thomas
> 
> Testing: gha, local testing, tier1-5 with other changes in this patch series, perf testing with other changes in this patch series

Thomas Schatzl has updated the pull request incrementally with one additional commit since the last revision:

  ayang review

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/10650/files
  - new: https://git.openjdk.org/jdk/pull/10650/files/35e6be38..5b6a3f93

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10650&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10650&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/10650.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10650/head:pull/10650

PR: https://git.openjdk.org/jdk/pull/10650