RFR: Borrow from old gen [v2]

Tue Feb 8 16:22:22 UTC 2022

> This commit represents multiple months of incremental performance improvements to allow generational shenandoah to run more efficiently, especially with larger heap sizes and high memory utilization.
> 
> Specific improvements are described in individual commit log messages.

Kelvin Nilsen has updated the pull request incrementally with one additional commit since the last revision:

  Respond to reviewer feedback

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Changes:
  - all: https://git.openjdk.java.net/shenandoah/pull/110/files
  - new: https://git.openjdk.java.net/shenandoah/pull/110/files/dc8a6654..4129539b

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=shenandoah&pr=110&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=shenandoah&pr=110&range=00-01

  Stats: 140 lines in 24 files changed: 44 ins; 51 del; 45 mod
  Patch: https://git.openjdk.java.net/shenandoah/pull/110.diff
  Fetch: git fetch https://git.openjdk.java.net/shenandoah pull/110/head:pull/110

PR: https://git.openjdk.java.net/shenandoah/pull/110